3:42 a.m.
Without the patch:
crash> log
...
[ 2174.308966] Call Trace:
[ 2174.311693] <TASK>
[ 2174.314033] dump_stack_lvl+0x5d/0x80
[ 2174.318125] panic+0x156/0x32a
[ 2174.321539] _RNvCscb18lrEyTSA_10rust_panic10area_in_hp+0xf7/0x120 [rust_panic]
[ 2174.329700] ? console_unlock+0x9c/0x140
[ 2174.334080] ? irq_work_queue+0x2d/0x50
[ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
[ 2174.344183] _RNvMCscb18lrEyTSA_10rust_panicNtB2_10HelloPanic8step_two+0x20/0xe0
[rust_panic]
[ 2174.353698] ? _printk+0x6b/0x90
...
With the patch:
crash> log
...
[ 2174.308966] Call Trace:
[ 2174.311693] <TASK>
[ 2174.314033] dump_stack_lvl+0x5d/0x80
[ 2174.318125] panic+0x156/0x32a
[ 2174.321539] rust_panic::area_in_hp+0xf7/0x120 [rust_panic]
[ 2174.329700] ? console_unlock+0x9c/0x140
[ 2174.334080] ? irq_work_queue+0x2d/0x50
[ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
[ 2174.344183] <rust_panic::HelloPanic>::step_two+0x20/0xe0 [rust_panic]
[ 2174.353698] ? _printk+0x6b/0x90
...
Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com>
---
Note:
1. Add some checks to avoid the risk of buffer overflow.
Makefile | 2 +-
printk.c | 33 ++++++++++++++++++++++++++++++++-
2 files changed, 33 insertions(+), 2 deletions(-)
diff --git a/Makefile b/Makefile
index fc1c9588dcfa..b277129f6df2 100644
--- a/Makefile
+++ b/Makefile
@@ -421,7 +421,7 @@ kernel.o: ${GENERIC_HFILES} kernel.c
${CC} -c ${CRASH_CFLAGS} kernel.c -I${BFD_DIRECTORY} -I${GDB_INCLUDE_DIRECTORY}
${WARNING_OPTIONS} ${WARNING_ERROR}
printk.o: ${GENERIC_HFILES} printk.c
- ${CC} -c ${CRASH_CFLAGS} printk.c ${WARNING_OPTIONS} ${WARNING_ERROR}
+ ${CC} -c ${CRASH_CFLAGS} printk.c -I${GDB_INCLUDE_DIRECTORY} ${WARNING_OPTIONS}
${WARNING_ERROR}
gdb_interface.o: ${GENERIC_HFILES} gdb_interface.c
${CC} -c ${CRASH_CFLAGS} gdb_interface.c ${WARNING_OPTIONS} ${WARNING_ERROR}
diff --git a/printk.c b/printk.c
index 95db7e607e4c..ae28c4fa0b21 100644
--- a/printk.c
+++ b/printk.c
@@ -1,5 +1,6 @@
#include "defs.h"
#include <ctype.h>
+#include "demangle.h"
/* convenience struct for passing many values to helper functions */
struct prb_map {
@@ -201,14 +202,44 @@ dump_record(struct prb_map *m, unsigned long id, int msg_flags)
text = m->text_data + begin;
+ if (text_len > BUFSIZE) {
+ error(WARNING, "\nThe messages could be truncated!\n");
+ text_len = BUFSIZE;
+ }
+
for (i = 0, p = text; i < text_len; i++, p++) {
if (*p == '\n')
fprintf(fp, "\n%s", space(ilen));
else if (isprint(*p) || isspace(*p))
- fputc(*p, fp);
+ sprintf(&buf[i], "%c", *p);
else
fputc('.', fp);
}
+ /*
+ * Try to demangle a mangled Rust symbol(calltrace) from log buffer
+ */
+ char *p1 = strstr(buf, "_R");
+ if (!p1)
+ p1 = strstr(buf, "_ZN");
+ char *p2 = strchrnul(buf, '+');
+ if (p1 && p2) {
+ char mangled[BUFSIZE] = {0};
+ char demangled[BUFSIZE] = {0};
+ char *res;
+ size_t slen = p1 - buf;
+
+ if (slen)
+ memcpy(demangled, buf, slen);
+
+ memcpy(mangled, p1, p2-p1);
+ res = rust_demangle(mangled, DMGL_RUST);
+ if (res) {
+ snprintf(demangled+slen, BUFSIZE-slen, "%s%s", res, p2);
+ fprintf(fp, "%s",demangled);
+ free(res);
+ }
+ } else
+ fprintf(fp, "%s", buf);
if (msg_flags & SHOW_LOG_DICT) {
text = info + OFFSET(printk_info_dev_info) +
--
2.50.1
9:33 p.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
Hi lianbo,
Thanks for the v2, LGTM, ack.
On Mon, Sep 8, 2025 at 8:42 PM Lianbo Jiang <lijiang(a)redhat.com> wrote:
Without the patch:
crash> log
...
[ 2174.308966] Call Trace:
[ 2174.311693] <TASK>
[ 2174.314033] dump_stack_lvl+0x5d/0x80
[ 2174.318125] panic+0x156/0x32a
[ 2174.321539] _RNvCscb18lrEyTSA_10rust_panic10area_in_hp+0xf7/0x120 [rust_panic]
[ 2174.329700] ? console_unlock+0x9c/0x140
[ 2174.334080] ? irq_work_queue+0x2d/0x50
[ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
[ 2174.344183] _RNvMCscb18lrEyTSA_10rust_panicNtB2_10HelloPanic8step_two+0x20/0xe0
[rust_panic]
[ 2174.353698] ? _printk+0x6b/0x90
...
With the patch:
crash> log
...
[ 2174.308966] Call Trace:
[ 2174.311693] <TASK>
[ 2174.314033] dump_stack_lvl+0x5d/0x80
[ 2174.318125] panic+0x156/0x32a
[ 2174.321539] rust_panic::area_in_hp+0xf7/0x120 [rust_panic]
[ 2174.329700] ? console_unlock+0x9c/0x140
[ 2174.334080] ? irq_work_queue+0x2d/0x50
[ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
[ 2174.344183] <rust_panic::HelloPanic>::step_two+0x20/0xe0 [rust_panic]
[ 2174.353698] ? _printk+0x6b/0x90
...
Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com>
---
Note:
1. Add some checks to avoid the risk of buffer overflow.
Makefile | 2 +-
printk.c | 33 ++++++++++++++++++++++++++++++++-
2 files changed, 33 insertions(+), 2 deletions(-)
diff --git a/Makefile b/Makefile
index fc1c9588dcfa..b277129f6df2 100644
--- a/Makefile
+++ b/Makefile
@@ -421,7 +421,7 @@ kernel.o: ${GENERIC_HFILES} kernel.c
${CC} -c ${CRASH_CFLAGS} kernel.c -I${BFD_DIRECTORY} -I${GDB_INCLUDE_DIRECTORY}
${WARNING_OPTIONS} ${WARNING_ERROR}
printk.o: ${GENERIC_HFILES} printk.c
- ${CC} -c ${CRASH_CFLAGS} printk.c ${WARNING_OPTIONS} ${WARNING_ERROR}
+ ${CC} -c ${CRASH_CFLAGS} printk.c -I${GDB_INCLUDE_DIRECTORY} ${WARNING_OPTIONS}
${WARNING_ERROR}
gdb_interface.o: ${GENERIC_HFILES} gdb_interface.c
${CC} -c ${CRASH_CFLAGS} gdb_interface.c ${WARNING_OPTIONS} ${WARNING_ERROR}
diff --git a/printk.c b/printk.c
index 95db7e607e4c..ae28c4fa0b21 100644
--- a/printk.c
+++ b/printk.c
@@ -1,5 +1,6 @@
#include "defs.h"
#include <ctype.h>
+#include "demangle.h"
/* convenience struct for passing many values to helper functions */
struct prb_map {
@@ -201,14 +202,44 @@ dump_record(struct prb_map *m, unsigned long id, int msg_flags)
text = m->text_data + begin;
+ if (text_len > BUFSIZE) {
+ error(WARNING, "\nThe messages could be truncated!\n");
+ text_len = BUFSIZE;
+ }
+
for (i = 0, p = text; i < text_len; i++, p++) {
if (*p == '\n')
fprintf(fp, "\n%s", space(ilen));
else if (isprint(*p) || isspace(*p))
- fputc(*p, fp);
+ sprintf(&buf[i], "%c", *p);
else
fputc('.', fp);
}
+ /*
+ * Try to demangle a mangled Rust symbol(calltrace) from log buffer
+ */
+ char *p1 = strstr(buf, "_R");
+ if (!p1)
+ p1 = strstr(buf, "_ZN");
+ char *p2 = strchrnul(buf, '+');
+ if (p1 && p2) {
+ char mangled[BUFSIZE] = {0};
+ char demangled[BUFSIZE] = {0};
+ char *res;
+ size_t slen = p1 - buf;
+
+ if (slen)
+ memcpy(demangled, buf, slen);
+
+ memcpy(mangled, p1, p2-p1);
+ res = rust_demangle(mangled, DMGL_RUST);
+ if (res) {
+ snprintf(demangled+slen, BUFSIZE-slen, "%s%s", res,
p2);
+ fprintf(fp, "%s",demangled);
+ free(res);
+ }
+ } else
+ fprintf(fp, "%s", buf);
if (msg_flags & SHOW_LOG_DICT) {
text = info + OFFSET(printk_info_dev_info) +
--
2.50.1
8:19 p.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
applied:
https://github.com/crash-utility/crash/commit/99bb57ac98afd89fcf23f0c8bc6...
On Wed, Sep 10, 2025 at 2:33 PM Tao Liu <ltao(a)redhat.com> wrote:
Hi lianbo,
Thanks for the v2, LGTM, ack.
On Mon, Sep 8, 2025 at 8:42 PM Lianbo Jiang <lijiang(a)redhat.com> wrote:
>
> Without the patch:
> crash> log
> ...
> [ 2174.308966] Call Trace:
> [ 2174.311693] <TASK>
> [ 2174.314033] dump_stack_lvl+0x5d/0x80
> [ 2174.318125] panic+0x156/0x32a
> [ 2174.321539] _RNvCscb18lrEyTSA_10rust_panic10area_in_hp+0xf7/0x120
[rust_panic]
> [ 2174.329700] ? console_unlock+0x9c/0x140
> [ 2174.334080] ? irq_work_queue+0x2d/0x50
> [ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
> [ 2174.344183]
_RNvMCscb18lrEyTSA_10rust_panicNtB2_10HelloPanic8step_two+0x20/0xe0 [rust_panic]
> [ 2174.353698] ? _printk+0x6b/0x90
> ...
>
> With the patch:
> crash> log
> ...
> [ 2174.308966] Call Trace:
> [ 2174.311693] <TASK>
> [ 2174.314033] dump_stack_lvl+0x5d/0x80
> [ 2174.318125] panic+0x156/0x32a
> [ 2174.321539] rust_panic::area_in_hp+0xf7/0x120 [rust_panic]
> [ 2174.329700] ? console_unlock+0x9c/0x140
> [ 2174.334080] ? irq_work_queue+0x2d/0x50
> [ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
> [ 2174.344183] <rust_panic::HelloPanic>::step_two+0x20/0xe0 [rust_panic]
> [ 2174.353698] ? _printk+0x6b/0x90
> ...
>
> Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com>
> ---
> Note:
> 1. Add some checks to avoid the risk of buffer overflow.
>
> Makefile | 2 +-
> printk.c | 33 ++++++++++++++++++++++++++++++++-
> 2 files changed, 33 insertions(+), 2 deletions(-)
>
> diff --git a/Makefile b/Makefile
> index fc1c9588dcfa..b277129f6df2 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -421,7 +421,7 @@ kernel.o: ${GENERIC_HFILES} kernel.c
> ${CC} -c ${CRASH_CFLAGS} kernel.c -I${BFD_DIRECTORY}
-I${GDB_INCLUDE_DIRECTORY} ${WARNING_OPTIONS} ${WARNING_ERROR}
>
> printk.o: ${GENERIC_HFILES} printk.c
> - ${CC} -c ${CRASH_CFLAGS} printk.c ${WARNING_OPTIONS} ${WARNING_ERROR}
> + ${CC} -c ${CRASH_CFLAGS} printk.c -I${GDB_INCLUDE_DIRECTORY}
${WARNING_OPTIONS} ${WARNING_ERROR}
>
> gdb_interface.o: ${GENERIC_HFILES} gdb_interface.c
> ${CC} -c ${CRASH_CFLAGS} gdb_interface.c ${WARNING_OPTIONS}
${WARNING_ERROR}
> diff --git a/printk.c b/printk.c
> index 95db7e607e4c..ae28c4fa0b21 100644
> --- a/printk.c
> +++ b/printk.c
> @@ -1,5 +1,6 @@
> #include "defs.h"
> #include <ctype.h>
> +#include "demangle.h"
>
> /* convenience struct for passing many values to helper functions */
> struct prb_map {
> @@ -201,14 +202,44 @@ dump_record(struct prb_map *m, unsigned long id, int
msg_flags)
>
> text = m->text_data + begin;
>
> + if (text_len > BUFSIZE) {
> + error(WARNING, "\nThe messages could be truncated!\n");
> + text_len = BUFSIZE;
> + }
> +
> for (i = 0, p = text; i < text_len; i++, p++) {
> if (*p == '\n')
> fprintf(fp, "\n%s", space(ilen));
> else if (isprint(*p) || isspace(*p))
> - fputc(*p, fp);
> + sprintf(&buf[i], "%c", *p);
> else
> fputc('.', fp);
> }
> + /*
> + * Try to demangle a mangled Rust symbol(calltrace) from log buffer
> + */
> + char *p1 = strstr(buf, "_R");
> + if (!p1)
> + p1 = strstr(buf, "_ZN");
> + char *p2 = strchrnul(buf, '+');
> + if (p1 && p2) {
> + char mangled[BUFSIZE] = {0};
> + char demangled[BUFSIZE] = {0};
> + char *res;
> + size_t slen = p1 - buf;
> +
> + if (slen)
> + memcpy(demangled, buf, slen);
> +
> + memcpy(mangled, p1, p2-p1);
> + res = rust_demangle(mangled, DMGL_RUST);
> + if (res) {
> + snprintf(demangled+slen, BUFSIZE-slen, "%s%s",
res, p2);
> + fprintf(fp, "%s",demangled);
> + free(res);
> + }
> + } else
> + fprintf(fp, "%s", buf);
>
> if (msg_flags & SHOW_LOG_DICT) {
> text = info + OFFSET(printk_info_dev_info) +
> --
> 2.50.1
>
11:51 p.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
Hi Lianbo, Tao,
Just a report, with this patch (99bb57ac98af), I observed that
the log command printed a couple of empty lines (only timestamps).
Could you reproduce this at your end?
$ diff -u log.pre log.cur
--- log.pre 2025-09-16 13:14:31.022206514 +0900
+++ log.cur 2025-09-16 13:14:56.220390987 +0900
@@ -210,7 +210,7 @@
[ 0.169375] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff,
max_idle_ns: 1911260446275000 ns
[ 0.169375] futex hash table entries: 1024 (order: 4, 65536 bytes, linear)
[ 0.169375] pinctrl core: initialized pinctrl subsystem
-[ 0.172925] NET: Registered PF_NETLINK/PF_ROUTE protocol family
+[ 0.172925]
[ 0.172983] DMA: preallocated 512 KiB GFP_KERNEL pool for atomic allocations
[ 0.172986] DMA: preallocated 512 KiB GFP_KERNEL|GFP_DMA pool for atomic
allocations
[ 0.172988] DMA: preallocated 512 KiB GFP_KERNEL|GFP_DMA32 pool for atomic
allocations
@@ -807,7 +807,7 @@
[771438.513231] entry_SYSCALL_64_after_hwframe+0x72/0xdc
[771438.513423] RIP: 0033:0x7fbd9f8fda57
[771438.513576] Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e
fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77
51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
-[771438.514251] RSP: 002b:00007ffee0de2b98 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
+[771438.514251]
[771438.514534] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fbd9f8fda57
[771438.514800] RDX: 0000000000000002 RSI: 00005647ccc0a330 RDI: 0000000000000001
[771438.515066] RBP: 00005647ccc0a330 R08: 0000000000000003 R09: 0000000000000000
log.cur: 99bb57ac98afd89fcf23f0c8bc637821dcbd278f
log.pre: a5942e3acfd9330d101cc65ef2e19e627233ddf6
vmcore: panic by sysrq-trigger on 5.14.0-427.13.1.el9_4.x86_64
(found also on 6.17-rc6)
Thanks,
Kazu
On 2025/09/15 10:19, Tao Liu wrote:
> applied:
https://github.com/crash-utility/crash/commit/99bb57ac98afd89fcf23f0c8bc6...
>
> On Wed, Sep 10, 2025 at 2:33 PM Tao Liu <ltao(a)redhat.com> wrote:
>>
>> Hi lianbo,
>>
>> Thanks for the v2, LGTM, ack.
>>
>>
>> On Mon, Sep 8, 2025 at 8:42 PM Lianbo Jiang <lijiang(a)redhat.com> wrote:
>>>
>>> Without the patch:
>>> crash> log
>>> ...
>>> [ 2174.308966] Call Trace:
>>> [ 2174.311693] <TASK>
>>> [ 2174.314033] dump_stack_lvl+0x5d/0x80
>>> [ 2174.318125] panic+0x156/0x32a
>>> [ 2174.321539] _RNvCscb18lrEyTSA_10rust_panic10area_in_hp+0xf7/0x120
[rust_panic]
>>> [ 2174.329700] ? console_unlock+0x9c/0x140
>>> [ 2174.334080] ? irq_work_queue+0x2d/0x50
>>> [ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
>>> [ 2174.344183]
_RNvMCscb18lrEyTSA_10rust_panicNtB2_10HelloPanic8step_two+0x20/0xe0 [rust_panic]
>>> [ 2174.353698] ? _printk+0x6b/0x90
>>> ...
>>>
>>> With the patch:
>>> crash> log
>>> ...
>>> [ 2174.308966] Call Trace:
>>> [ 2174.311693] <TASK>
>>> [ 2174.314033] dump_stack_lvl+0x5d/0x80
>>> [ 2174.318125] panic+0x156/0x32a
>>> [ 2174.321539] rust_panic::area_in_hp+0xf7/0x120 [rust_panic]
>>> [ 2174.329700] ? console_unlock+0x9c/0x140
>>> [ 2174.334080] ? irq_work_queue+0x2d/0x50
>>> [ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
>>> [ 2174.344183] <rust_panic::HelloPanic>::step_two+0x20/0xe0
[rust_panic]
>>> [ 2174.353698] ? _printk+0x6b/0x90
>>> ...
>>>
>>> Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com>
>>> ---
>>> Note:
>>> 1. Add some checks to avoid the risk of buffer overflow.
>>>
>>> Makefile | 2 +-
>>> printk.c | 33 ++++++++++++++++++++++++++++++++-
>>> 2 files changed, 33 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/Makefile b/Makefile
>>> index fc1c9588dcfa..b277129f6df2 100644
>>> --- a/Makefile
>>> +++ b/Makefile
>>> @@ -421,7 +421,7 @@ kernel.o: ${GENERIC_HFILES} kernel.c
>>> ${CC} -c ${CRASH_CFLAGS} kernel.c -I${BFD_DIRECTORY}
-I${GDB_INCLUDE_DIRECTORY} ${WARNING_OPTIONS} ${WARNING_ERROR}
>>>
>>> printk.o: ${GENERIC_HFILES} printk.c
>>> - ${CC} -c ${CRASH_CFLAGS} printk.c ${WARNING_OPTIONS}
${WARNING_ERROR}
>>> + ${CC} -c ${CRASH_CFLAGS} printk.c -I${GDB_INCLUDE_DIRECTORY}
${WARNING_OPTIONS} ${WARNING_ERROR}
>>>
>>> gdb_interface.o: ${GENERIC_HFILES} gdb_interface.c
>>> ${CC} -c ${CRASH_CFLAGS} gdb_interface.c ${WARNING_OPTIONS}
${WARNING_ERROR}
>>> diff --git a/printk.c b/printk.c
>>> index 95db7e607e4c..ae28c4fa0b21 100644
>>> --- a/printk.c
>>> +++ b/printk.c
>>> @@ -1,5 +1,6 @@
>>> #include "defs.h"
>>> #include <ctype.h>
>>> +#include "demangle.h"
>>>
>>> /* convenience struct for passing many values to helper functions */
>>> struct prb_map {
>>> @@ -201,14 +202,44 @@ dump_record(struct prb_map *m, unsigned long id, int
msg_flags)
>>>
>>> text = m->text_data + begin;
>>>
>>> + if (text_len > BUFSIZE) {
>>> + error(WARNING, "\nThe messages could be
truncated!\n");
>>> + text_len = BUFSIZE;
>>> + }
>>> +
>>> for (i = 0, p = text; i < text_len; i++, p++) {
>>> if (*p == '\n')
>>> fprintf(fp, "\n%s", space(ilen));
>>> else if (isprint(*p) || isspace(*p))
>>> - fputc(*p, fp);
>>> + sprintf(&buf[i], "%c", *p);
>>> else
>>> fputc('.', fp);
>>> }
>>> + /*
>>> + * Try to demangle a mangled Rust symbol(calltrace) from log buffer
>>> + */
>>> + char *p1 = strstr(buf, "_R");
>>> + if (!p1)
>>> + p1 = strstr(buf, "_ZN");
>>> + char *p2 = strchrnul(buf, '+');
>>> + if (p1 && p2) {
>>> + char mangled[BUFSIZE] = {0};
>>> + char demangled[BUFSIZE] = {0};
>>> + char *res;
>>> + size_t slen = p1 - buf;
>>> +
>>> + if (slen)
>>> + memcpy(demangled, buf, slen);
>>> +
>>> + memcpy(mangled, p1, p2-p1);
>>> + res = rust_demangle(mangled, DMGL_RUST);
>>> + if (res) {
>>> + snprintf(demangled+slen, BUFSIZE-slen,
"%s%s", res, p2);
>>> + fprintf(fp, "%s",demangled);
>>> + free(res);
>>> + }
>>> + } else
>>> + fprintf(fp, "%s", buf);
>>>
>>> if (msg_flags & SHOW_LOG_DICT) {
>>> text = info + OFFSET(printk_info_dev_info) +
>>> --
>>> 2.50.1
>>>
> --
> Crash-utility mailing list -- devel(a)lists.crash-utility.osci.io
> To unsubscribe send an email to devel-leave(a)lists.crash-utility.osci.io
> https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/
> Contribution Guidelines: https://github.com/crash-utility/crash/wiki
1:26 a.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
On Tue, Sep 16, 2025 at 12:51 PM HAGIO KAZUHITO(萩尾 一仁) <k-hagio-ab(a)nec.com>
wrote:
Hi Lianbo, Tao,
Just a report, with this patch (99bb57ac98af), I observed that
the log command printed a couple of empty lines (only timestamps).
Could you reproduce this at your end?
Thank you for reporting this, Kazu.
I will check it, and did not see it before this.
Thanks.
Lianbo
$ diff -u log.pre log.cur
--- log.pre 2025-09-16 13:14:31.022206514 +0900
+++ log.cur 2025-09-16 13:14:56.220390987 +0900
@@ -210,7 +210,7 @@
[ 0.169375] clocksource: jiffies: mask: 0xffffffff max_cycles:
0xffffffff, max_idle_ns: 1911260446275000 ns
[ 0.169375] futex hash table entries: 1024 (order: 4, 65536 bytes,
linear)
[ 0.169375] pinctrl core: initialized pinctrl subsystem
-[ 0.172925] NET: Registered PF_NETLINK/PF_ROUTE protocol family
+[ 0.172925]
[ 0.172983] DMA: preallocated 512 KiB GFP_KERNEL pool for atomic
allocations
[ 0.172986] DMA: preallocated 512 KiB GFP_KERNEL|GFP_DMA pool for
atomic allocations
[ 0.172988] DMA: preallocated 512 KiB GFP_KERNEL|GFP_DMA32 pool for
atomic allocations
@@ -807,7 +807,7 @@
[771438.513231] entry_SYSCALL_64_after_hwframe+0x72/0xdc
[771438.513423] RIP: 0033:0x7fbd9f8fda57
[771438.513576] Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f
1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05
<48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
-[771438.514251] RSP: 002b:00007ffee0de2b98 EFLAGS: 00000246 ORIG_RAX:
0000000000000001
+[771438.514251]
[771438.514534] RAX: ffffffffffffffda RBX: 0000000000000002 RCX:
00007fbd9f8fda57
[771438.514800] RDX: 0000000000000002 RSI: 00005647ccc0a330 RDI:
0000000000000001
[771438.515066] RBP: 00005647ccc0a330 R08: 0000000000000003 R09:
0000000000000000
log.cur: 99bb57ac98afd89fcf23f0c8bc637821dcbd278f
log.pre: a5942e3acfd9330d101cc65ef2e19e627233ddf6
vmcore: panic by sysrq-trigger on 5.14.0-427.13.1.el9_4.x86_64
(found also on 6.17-rc6)
Thanks,
Kazu
On 2025/09/15 10:19, Tao Liu wrote:
> applied:
https://github.com/crash-utility/crash/commit/99bb57ac98afd89fcf23f0c8bc6...
>
> On Wed, Sep 10, 2025 at 2:33 PM Tao Liu <ltao(a)redhat.com> wrote:
>>
>> Hi lianbo,
>>
>> Thanks for the v2, LGTM, ack.
>>
>>
>> On Mon, Sep 8, 2025 at 8:42 PM Lianbo Jiang <lijiang(a)redhat.com> wrote:
>>>
>>> Without the patch:
>>> crash> log
>>> ...
>>> [ 2174.308966] Call Trace:
>>> [ 2174.311693] <TASK>
>>> [ 2174.314033] dump_stack_lvl+0x5d/0x80
>>> [ 2174.318125] panic+0x156/0x32a
>>> [ 2174.321539]
_RNvCscb18lrEyTSA_10rust_panic10area_in_hp+0xf7/0x120 [rust_panic]
>>> [ 2174.329700] ? console_unlock+0x9c/0x140
>>> [ 2174.334080] ? irq_work_queue+0x2d/0x50
>>> [ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
>>> [ 2174.344183]
_RNvMCscb18lrEyTSA_10rust_panicNtB2_10HelloPanic8step_two+0x20/0xe0
[rust_panic]
>>> [ 2174.353698] ? _printk+0x6b/0x90
>>> ...
>>>
>>> With the patch:
>>> crash> log
>>> ...
>>> [ 2174.308966] Call Trace:
>>> [ 2174.311693] <TASK>
>>> [ 2174.314033] dump_stack_lvl+0x5d/0x80
>>> [ 2174.318125] panic+0x156/0x32a
>>> [ 2174.321539] rust_panic::area_in_hp+0xf7/0x120 [rust_panic]
>>> [ 2174.329700] ? console_unlock+0x9c/0x140
>>> [ 2174.334080] ? irq_work_queue+0x2d/0x50
>>> [ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
>>> [ 2174.344183] <rust_panic::HelloPanic>::step_two+0x20/0xe0
[rust_panic]
>>> [ 2174.353698] ? _printk+0x6b/0x90
>>> ...
>>>
>>> Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com>
>>> ---
>>> Note:
>>> 1. Add some checks to avoid the risk of buffer overflow.
>>>
>>> Makefile | 2 +-
>>> printk.c | 33 ++++++++++++++++++++++++++++++++-
>>> 2 files changed, 33 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/Makefile b/Makefile
>>> index fc1c9588dcfa..b277129f6df2 100644
>>> --- a/Makefile
>>> +++ b/Makefile
>>> @@ -421,7 +421,7 @@ kernel.o: ${GENERIC_HFILES} kernel.c
>>> ${CC} -c ${CRASH_CFLAGS} kernel.c -I${BFD_DIRECTORY}
-I${GDB_INCLUDE_DIRECTORY} ${WARNING_OPTIONS} ${WARNING_ERROR}
>>>
>>> printk.o: ${GENERIC_HFILES} printk.c
>>> - ${CC} -c ${CRASH_CFLAGS} printk.c ${WARNING_OPTIONS}
${WARNING_ERROR}
>>> + ${CC} -c ${CRASH_CFLAGS} printk.c -I${GDB_INCLUDE_DIRECTORY}
${WARNING_OPTIONS} ${WARNING_ERROR}
>>>
>>> gdb_interface.o: ${GENERIC_HFILES} gdb_interface.c
>>> ${CC} -c ${CRASH_CFLAGS} gdb_interface.c ${WARNING_OPTIONS}
${WARNING_ERROR}
>>> diff --git a/printk.c b/printk.c
>>> index 95db7e607e4c..ae28c4fa0b21 100644
>>> --- a/printk.c
>>> +++ b/printk.c
>>> @@ -1,5 +1,6 @@
>>> #include "defs.h"
>>> #include <ctype.h>
>>> +#include "demangle.h"
>>>
>>> /* convenience struct for passing many values to helper functions */
>>> struct prb_map {
>>> @@ -201,14 +202,44 @@ dump_record(struct prb_map *m, unsigned long id,
int msg_flags)
>>>
>>> text = m->text_data + begin;
>>>
>>> + if (text_len > BUFSIZE) {
>>> + error(WARNING, "\nThe messages could be
truncated!\n");
>>> + text_len = BUFSIZE;
>>> + }
>>> +
>>> for (i = 0, p = text; i < text_len; i++, p++) {
>>> if (*p == '\n')
>>> fprintf(fp, "\n%s", space(ilen));
>>> else if (isprint(*p) || isspace(*p))
>>> - fputc(*p, fp);
>>> + sprintf(&buf[i], "%c", *p);
>>> else
>>> fputc('.', fp);
>>> }
>>> + /*
>>> + * Try to demangle a mangled Rust symbol(calltrace) from log
buffer
>>> + */
>>> + char *p1 = strstr(buf, "_R");
>>> + if (!p1)
>>> + p1 = strstr(buf, "_ZN");
>>> + char *p2 = strchrnul(buf, '+');
>>> + if (p1 && p2) {
>>> + char mangled[BUFSIZE] = {0};
>>> + char demangled[BUFSIZE] = {0};
>>> + char *res;
>>> + size_t slen = p1 - buf;
>>> +
>>> + if (slen)
>>> + memcpy(demangled, buf, slen);
>>> +
>>> + memcpy(mangled, p1, p2-p1);
>>> + res = rust_demangle(mangled, DMGL_RUST);
>>> + if (res) {
>>> + snprintf(demangled+slen, BUFSIZE-slen,
"%s%s",
res, p2);
>>> + fprintf(fp, "%s",demangled);
>>> + free(res);
>>> + }
>>> + } else
>>> + fprintf(fp, "%s", buf);
>>>
>>> if (msg_flags & SHOW_LOG_DICT) {
>>> text = info + OFFSET(printk_info_dev_info) +
>>> --
>>> 2.50.1
>>>
> --
> Crash-utility mailing list -- devel(a)lists.crash-utility.osci.io
> To unsubscribe send an email to devel-leave(a)lists.crash-utility.osci.io
> https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/
> Contribution Guidelines: https://github.com/crash-utility/crash/wiki
2:37 a.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
On Tue, Sep 16, 2025 at 2:26 PM lijiang <lijiang(a)redhat.com> wrote:
On Tue, Sep 16, 2025 at 12:51 PM HAGIO KAZUHITO(萩尾 一仁)
<k-hagio-ab(a)nec.com>
wrote:
> Hi Lianbo, Tao,
>
> Just a report, with this patch (99bb57ac98af), I observed that
> the log command printed a couple of empty lines (only timestamps).
> Could you reproduce this at your end?
>
Thank you for reporting this, Kazu.
I will check it, and did not see it before this.
Could you please try this one? Kazu.
diff --git a/printk.c b/printk.c
index ae28c4f..51b618e 100644
--- a/printk.c
+++ b/printk.c
@@ -221,7 +221,7 @@ dump_record(struct prb_map *m, unsigned long id, int
msg_flags)
char *p1 = strstr(buf, "_R");
if (!p1)
p1 = strstr(buf, "_ZN");
- char *p2 = strchrnul(buf, '+');
+ char *p2 = strrchr(buf, '+');
if (p1 && p2) {
char mangled[BUFSIZE] = {0};
char demangled[BUFSIZE] = {0};
I did not reproduce it, but I guess that this should be related to the
strchrnul(), let's replace it with the strrchr().
Thanks.
Lianbo
Thanks.
Lianbo
> $ diff -u log.pre log.cur
> --- log.pre 2025-09-16 13:14:31.022206514 +0900
> +++ log.cur 2025-09-16 13:14:56.220390987 +0900
> @@ -210,7 +210,7 @@
> [ 0.169375] clocksource: jiffies: mask: 0xffffffff max_cycles:
> 0xffffffff, max_idle_ns: 1911260446275000 ns
> [ 0.169375] futex hash table entries: 1024 (order: 4, 65536 bytes,
> linear)
> [ 0.169375] pinctrl core: initialized pinctrl subsystem
> -[ 0.172925] NET: Registered PF_NETLINK/PF_ROUTE protocol family
> +[ 0.172925]
> [ 0.172983] DMA: preallocated 512 KiB GFP_KERNEL pool for atomic
> allocations
> [ 0.172986] DMA: preallocated 512 KiB GFP_KERNEL|GFP_DMA pool for
> atomic allocations
> [ 0.172988] DMA: preallocated 512 KiB GFP_KERNEL|GFP_DMA32 pool for
> atomic allocations
> @@ -807,7 +807,7 @@
> [771438.513231] entry_SYSCALL_64_after_hwframe+0x72/0xdc
> [771438.513423] RIP: 0033:0x7fbd9f8fda57
> [771438.513576] Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7
> 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f
> 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
> -[771438.514251] RSP: 002b:00007ffee0de2b98 EFLAGS: 00000246 ORIG_RAX:
> 0000000000000001
> +[771438.514251]
> [771438.514534] RAX: ffffffffffffffda RBX: 0000000000000002 RCX:
> 00007fbd9f8fda57
> [771438.514800] RDX: 0000000000000002 RSI: 00005647ccc0a330 RDI:
> 0000000000000001
> [771438.515066] RBP: 00005647ccc0a330 R08: 0000000000000003 R09:
> 0000000000000000
>
> log.cur: 99bb57ac98afd89fcf23f0c8bc637821dcbd278f
> log.pre: a5942e3acfd9330d101cc65ef2e19e627233ddf6
> vmcore: panic by sysrq-trigger on 5.14.0-427.13.1.el9_4.x86_64
> (found also on 6.17-rc6)
>
> Thanks,
> Kazu
>
> On 2025/09/15 10:19, Tao Liu wrote:
> > applied:
>
https://github.com/crash-utility/crash/commit/99bb57ac98afd89fcf23f0c8bc6...
> >
> > On Wed, Sep 10, 2025 at 2:33 PM Tao Liu <ltao(a)redhat.com> wrote:
> >>
> >> Hi lianbo,
> >>
> >> Thanks for the v2, LGTM, ack.
> >>
> >>
> >> On Mon, Sep 8, 2025 at 8:42 PM Lianbo Jiang <lijiang(a)redhat.com>
> wrote:
> >>>
> >>> Without the patch:
> >>> crash> log
> >>> ...
> >>> [ 2174.308966] Call Trace:
> >>> [ 2174.311693] <TASK>
> >>> [ 2174.314033] dump_stack_lvl+0x5d/0x80
> >>> [ 2174.318125] panic+0x156/0x32a
> >>> [ 2174.321539]
> _RNvCscb18lrEyTSA_10rust_panic10area_in_hp+0xf7/0x120 [rust_panic]
> >>> [ 2174.329700] ? console_unlock+0x9c/0x140
> >>> [ 2174.334080] ? irq_work_queue+0x2d/0x50
> >>> [ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
> >>> [ 2174.344183]
> _RNvMCscb18lrEyTSA_10rust_panicNtB2_10HelloPanic8step_two+0x20/0xe0
> [rust_panic]
> >>> [ 2174.353698] ? _printk+0x6b/0x90
> >>> ...
> >>>
> >>> With the patch:
> >>> crash> log
> >>> ...
> >>> [ 2174.308966] Call Trace:
> >>> [ 2174.311693] <TASK>
> >>> [ 2174.314033] dump_stack_lvl+0x5d/0x80
> >>> [ 2174.318125] panic+0x156/0x32a
> >>> [ 2174.321539] rust_panic::area_in_hp+0xf7/0x120 [rust_panic]
> >>> [ 2174.329700] ? console_unlock+0x9c/0x140
> >>> [ 2174.334080] ? irq_work_queue+0x2d/0x50
> >>> [ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
> >>> [ 2174.344183] <rust_panic::HelloPanic>::step_two+0x20/0xe0
> [rust_panic]
> >>> [ 2174.353698] ? _printk+0x6b/0x90
> >>> ...
> >>>
> >>> Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com>
> >>> ---
> >>> Note:
> >>> 1. Add some checks to avoid the risk of buffer overflow.
> >>>
> >>> Makefile | 2 +-
> >>> printk.c | 33 ++++++++++++++++++++++++++++++++-
> >>> 2 files changed, 33 insertions(+), 2 deletions(-)
> >>>
> >>> diff --git a/Makefile b/Makefile
> >>> index fc1c9588dcfa..b277129f6df2 100644
> >>> --- a/Makefile
> >>> +++ b/Makefile
> >>> @@ -421,7 +421,7 @@ kernel.o: ${GENERIC_HFILES} kernel.c
> >>> ${CC} -c ${CRASH_CFLAGS} kernel.c -I${BFD_DIRECTORY}
> -I${GDB_INCLUDE_DIRECTORY} ${WARNING_OPTIONS} ${WARNING_ERROR}
> >>>
> >>> printk.o: ${GENERIC_HFILES} printk.c
> >>> - ${CC} -c ${CRASH_CFLAGS} printk.c ${WARNING_OPTIONS}
> ${WARNING_ERROR}
> >>> + ${CC} -c ${CRASH_CFLAGS} printk.c -I${GDB_INCLUDE_DIRECTORY}
> ${WARNING_OPTIONS} ${WARNING_ERROR}
> >>>
> >>> gdb_interface.o: ${GENERIC_HFILES} gdb_interface.c
> >>> ${CC} -c ${CRASH_CFLAGS} gdb_interface.c ${WARNING_OPTIONS}
> ${WARNING_ERROR}
> >>> diff --git a/printk.c b/printk.c
> >>> index 95db7e607e4c..ae28c4fa0b21 100644
> >>> --- a/printk.c
> >>> +++ b/printk.c
> >>> @@ -1,5 +1,6 @@
> >>> #include "defs.h"
> >>> #include <ctype.h>
> >>> +#include "demangle.h"
> >>>
> >>> /* convenience struct for passing many values to helper functions */
> >>> struct prb_map {
> >>> @@ -201,14 +202,44 @@ dump_record(struct prb_map *m, unsigned long
> id, int msg_flags)
> >>>
> >>> text = m->text_data + begin;
> >>>
> >>> + if (text_len > BUFSIZE) {
> >>> + error(WARNING, "\nThe messages could be
> truncated!\n");
> >>> + text_len = BUFSIZE;
> >>> + }
> >>> +
> >>> for (i = 0, p = text; i < text_len; i++, p++) {
> >>> if (*p == '\n')
> >>> fprintf(fp, "\n%s", space(ilen));
> >>> else if (isprint(*p) || isspace(*p))
> >>> - fputc(*p, fp);
> >>> + sprintf(&buf[i], "%c", *p);
> >>> else
> >>> fputc('.', fp);
> >>> }
> >>> + /*
> >>> + * Try to demangle a mangled Rust symbol(calltrace) from log
> buffer
> >>> + */
> >>> + char *p1 = strstr(buf, "_R");
> >>> + if (!p1)
> >>> + p1 = strstr(buf, "_ZN");
> >>> + char *p2 = strchrnul(buf, '+');
> >>> + if (p1 && p2) {
> >>> + char mangled[BUFSIZE] = {0};
> >>> + char demangled[BUFSIZE] = {0};
> >>> + char *res;
> >>> + size_t slen = p1 - buf;
> >>> +
> >>> + if (slen)
> >>> + memcpy(demangled, buf, slen);
> >>> +
> >>> + memcpy(mangled, p1, p2-p1);
> >>> + res = rust_demangle(mangled, DMGL_RUST);
> >>> + if (res) {
> >>> + snprintf(demangled+slen, BUFSIZE-slen,
> "%s%s", res, p2);
> >>> + fprintf(fp, "%s",demangled);
> >>> + free(res);
> >>> + }
> >>> + } else
> >>> + fprintf(fp, "%s", buf);
> >>>
> >>> if (msg_flags & SHOW_LOG_DICT) {
> >>> text = info + OFFSET(printk_info_dev_info) +
> >>> --
> >>> 2.50.1
> >>>
> > --
> > Crash-utility mailing list -- devel(a)lists.crash-utility.osci.io
> > To unsubscribe send an email to devel-leave(a)lists.crash-utility.osci.io
> > https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/
> > Contribution Guidelines: https://github.com/crash-utility/crash/wiki
3:19 a.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
On 2025/09/16 16:37, lijiang wrote:
On Tue, Sep 16, 2025 at 2:26 PM lijiang <lijiang(a)redhat.com
<mailto:lijiang@redhat.com>> wrote:
On Tue, Sep 16, 2025 at 12:51 PM HAGIO KAZUHITO(萩尾 一仁) <k-hagio-ab(a)nec.com
<mailto:k-hagio-ab@nec.com>> wrote:
Hi Lianbo, Tao,
Just a report, with this patch (99bb57ac98af), I observed that
the log command printed a couple of empty lines (only timestamps).
Could you reproduce this at your end?
Thank you for reporting this, Kazu.
I will check it, and did not see it before this.
Could you please try this one? Kazu.
Sure, the patch below fixed the issue at my end.
Thanks,
Kazu
>
> diff --git a/printk.c b/printk.c
> index ae28c4f..51b618e 100644
> --- a/printk.c
> +++ b/printk.c
> @@ -221,7 +221,7 @@ dump_record(struct prb_map *m, unsigned long id, int msg_flags)
> char *p1 = strstr(buf, "_R");
> if (!p1)
> p1 = strstr(buf, "_ZN");
> - char *p2 = strchrnul(buf, '+');
> + char *p2 = strrchr(buf, '+');
> if (p1 && p2) {
> char mangled[BUFSIZE] = {0};
> char demangled[BUFSIZE] = {0};
>
> I did not reproduce it, but I guess that this should be related to the strchrnul(),
let's replace it with the strrchr().
>
> Thanks.
> Lianbo
>
>
> Thanks.
> Lianbo
>
>
> $ diff -u log.pre log.cur
> --- log.pre 2025-09-16 13:14:31.022206514 +0900
> +++ log.cur 2025-09-16 13:14:56.220390987 +0900
> @@ -210,7 +210,7 @@
> [ 0.169375] clocksource: jiffies: mask: 0xffffffff max_cycles:
0xffffffff, max_idle_ns: 1911260446275000 ns
> [ 0.169375] futex hash table entries: 1024 (order: 4, 65536 bytes,
linear)
> [ 0.169375] pinctrl core: initialized pinctrl subsystem
> -[ 0.172925] NET: Registered PF_NETLINK/PF_ROUTE protocol family
> +[ 0.172925]
> [ 0.172983] DMA: preallocated 512 KiB GFP_KERNEL pool for atomic
allocations
> [ 0.172986] DMA: preallocated 512 KiB GFP_KERNEL|GFP_DMA pool for
atomic allocations
> [ 0.172988] DMA: preallocated 512 KiB GFP_KERNEL|GFP_DMA32 pool for
atomic allocations
> @@ -807,7 +807,7 @@
> [771438.513231] entry_SYSCALL_64_after_hwframe+0x72/0xdc
> [771438.513423] RIP: 0033:0x7fbd9f8fda57
> [771438.513576] Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f
1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d
00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
> -[771438.514251] RSP: 002b:00007ffee0de2b98 EFLAGS: 00000246 ORIG_RAX:
0000000000000001
> +[771438.514251]
> [771438.514534] RAX: ffffffffffffffda RBX: 0000000000000002 RCX:
00007fbd9f8fda57
> [771438.514800] RDX: 0000000000000002 RSI: 00005647ccc0a330 RDI:
0000000000000001
> [771438.515066] RBP: 00005647ccc0a330 R08: 0000000000000003 R09:
0000000000000000
>
> log.cur: 99bb57ac98afd89fcf23f0c8bc637821dcbd278f
> log.pre: a5942e3acfd9330d101cc65ef2e19e627233ddf6
> vmcore: panic by sysrq-trigger on 5.14.0-427.13.1.el9_4.x86_64
> (found also on 6.17-rc6)
>
> Thanks,
> Kazu
>
> On 2025/09/15 10:19, Tao Liu wrote:
> > applied:
https://github.com/crash-utility/crash/commit/99bb57ac98afd89fcf23f0c8bc6...
<https://github.com/crash-utility/crash/commit/99bb57ac98afd89fcf23f0c8bc6...
> >
> > On Wed, Sep 10, 2025 at 2:33 PM Tao Liu <ltao(a)redhat.com
<mailto:ltao@redhat.com>> wrote:
> >>
> >> Hi lianbo,
> >>
> >> Thanks for the v2, LGTM, ack.
> >>
> >>
> >> On Mon, Sep 8, 2025 at 8:42 PM Lianbo Jiang <lijiang(a)redhat.com
<mailto:lijiang@redhat.com>> wrote:
> >>>
> >>> Without the patch:
> >>> crash> log
> >>> ...
> >>> [ 2174.308966] Call Trace:
> >>> [ 2174.311693] <TASK>
> >>> [ 2174.314033] dump_stack_lvl+0x5d/0x80
> >>> [ 2174.318125] panic+0x156/0x32a
> >>> [ 2174.321539]
_RNvCscb18lrEyTSA_10rust_panic10area_in_hp+0xf7/0x120 [rust_panic]
> >>> [ 2174.329700] ? console_unlock+0x9c/0x140
> >>> [ 2174.334080] ? irq_work_queue+0x2d/0x50
> >>> [ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
> >>> [ 2174.344183]
_RNvMCscb18lrEyTSA_10rust_panicNtB2_10HelloPanic8step_two+0x20/0xe0 [rust_panic]
> >>> [ 2174.353698] ? _printk+0x6b/0x90
> >>> ...
> >>>
> >>> With the patch:
> >>> crash> log
> >>> ...
> >>> [ 2174.308966] Call Trace:
> >>> [ 2174.311693] <TASK>
> >>> [ 2174.314033] dump_stack_lvl+0x5d/0x80
> >>> [ 2174.318125] panic+0x156/0x32a
> >>> [ 2174.321539] rust_panic::area_in_hp+0xf7/0x120
[rust_panic]
> >>> [ 2174.329700] ? console_unlock+0x9c/0x140
> >>> [ 2174.334080] ? irq_work_queue+0x2d/0x50
> >>> [ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
> >>> [ 2174.344183]
<rust_panic::HelloPanic>::step_two+0x20/0xe0 [rust_panic]
> >>> [ 2174.353698] ? _printk+0x6b/0x90
> >>> ...
> >>>
> >>> Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com
<mailto:lijiang@redhat.com>>
> >>> ---
> >>> Note:
> >>> 1. Add some checks to avoid the risk of buffer overflow.
> >>>
> >>> Makefile | 2 +-
> >>> printk.c | 33 ++++++++++++++++++++++++++++++++-
> >>> 2 files changed, 33 insertions(+), 2 deletions(-)
> >>>
> >>> diff --git a/Makefile b/Makefile
> >>> index fc1c9588dcfa..b277129f6df2 100644
> >>> --- a/Makefile
> >>> +++ b/Makefile
> >>> @@ -421,7 +421,7 @@ kernel.o: ${GENERIC_HFILES} kernel.c
> >>> ${CC} -c ${CRASH_CFLAGS} kernel.c -I${BFD_DIRECTORY}
-I${GDB_INCLUDE_DIRECTORY} ${WARNING_OPTIONS} ${WARNING_ERROR}
> >>>
> >>> printk.o: ${GENERIC_HFILES} printk.c
> >>> - ${CC} -c ${CRASH_CFLAGS} printk.c ${WARNING_OPTIONS}
${WARNING_ERROR}
> >>> + ${CC} -c ${CRASH_CFLAGS} printk.c
-I${GDB_INCLUDE_DIRECTORY} ${WARNING_OPTIONS} ${WARNING_ERROR}
> >>>
> >>> gdb_interface.o: ${GENERIC_HFILES} gdb_interface.c
> >>> ${CC} -c ${CRASH_CFLAGS} gdb_interface.c
${WARNING_OPTIONS} ${WARNING_ERROR}
> >>> diff --git a/printk.c b/printk.c
> >>> index 95db7e607e4c..ae28c4fa0b21 100644
> >>> --- a/printk.c
> >>> +++ b/printk.c
> >>> @@ -1,5 +1,6 @@
> >>> #include "defs.h"
> >>> #include <ctype.h>
> >>> +#include "demangle.h"
> >>>
> >>> /* convenience struct for passing many values to helper
functions */
> >>> struct prb_map {
> >>> @@ -201,14 +202,44 @@ dump_record(struct prb_map *m, unsigned
long id, int msg_flags)
> >>>
> >>> text = m->text_data + begin;
> >>>
> >>> + if (text_len > BUFSIZE) {
> >>> + error(WARNING, "\nThe messages could be
truncated!\n");
> >>> + text_len = BUFSIZE;
> >>> + }
> >>> +
> >>> for (i = 0, p = text; i < text_len; i++, p++) {
> >>> if (*p == '\n')
> >>> fprintf(fp, "\n%s",
space(ilen));
> >>> else if (isprint(*p) || isspace(*p))
> >>> - fputc(*p, fp);
> >>> + sprintf(&buf[i], "%c",
*p);
> >>> else
> >>> fputc('.', fp);
> >>> }
> >>> + /*
> >>> + * Try to demangle a mangled Rust symbol(calltrace)
from log buffer
> >>> + */
> >>> + char *p1 = strstr(buf, "_R");
> >>> + if (!p1)
> >>> + p1 = strstr(buf, "_ZN");
> >>> + char *p2 = strchrnul(buf, '+');
> >>> + if (p1 && p2) {
> >>> + char mangled[BUFSIZE] = {0};
> >>> + char demangled[BUFSIZE] = {0};
> >>> + char *res;
> >>> + size_t slen = p1 - buf;
> >>> +
> >>> + if (slen)
> >>> + memcpy(demangled, buf, slen);
> >>> +
> >>> + memcpy(mangled, p1, p2-p1);
> >>> + res = rust_demangle(mangled, DMGL_RUST);
> >>> + if (res) {
> >>> + snprintf(demangled+slen, BUFSIZE-slen,
"%s%s", res, p2);
> >>> + fprintf(fp,
"%s",demangled);
> >>> + free(res);
> >>> + }
> >>> + } else
> >>> + fprintf(fp, "%s", buf);
> >>>
> >>> if (msg_flags & SHOW_LOG_DICT) {
> >>> text = info + OFFSET(printk_info_dev_info) +
> >>> --
> >>> 2.50.1
> >>>
> > --
> > Crash-utility mailing list -- devel(a)lists.crash-utility.osci.io
<mailto:devel@lists.crash-utility.osci.io>
> > To unsubscribe send an email to devel-leave(a)lists.crash-utility.osci.io
<mailto:devel-leave@lists.crash-utility.osci.io>
> > https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/
<http://devel.lists.crash-utility.osci.io/>
> > Contribution Guidelines: https://github.com/crash-utility/crash/wiki
<https://github.com/crash-utility/crash/wiki>
>
3:27 a.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
On Tue, Sep 16, 2025 at 4:19 PM HAGIO KAZUHITO(萩尾 一仁) <k-hagio-ab(a)nec.com>
wrote:
On 2025/09/16 16:37, lijiang wrote:
> On Tue, Sep 16, 2025 at 2:26 PM lijiang <lijiang(a)redhat.com <mailto:
lijiang(a)redhat.com>> wrote:
>
> On Tue, Sep 16, 2025 at 12:51 PM HAGIO KAZUHITO(萩尾 一仁) <
k-hagio-ab(a)nec.com <mailto:k-hagio-ab@nec.com>> wrote:
>
> Hi Lianbo, Tao,
>
> Just a report, with this patch (99bb57ac98af), I observed that
> the log command printed a couple of empty lines (only
timestamps).
> Could you reproduce this at your end?
>
>
> Thank you for reporting this, Kazu.
> I will check it, and did not see it before this.
>
> Could you please try this one? Kazu.
Sure, the patch below fixed the issue at my end.
Good news.
Thank you so much, Kazu.
Lianbo
Thanks,
Kazu
>
> diff --git a/printk.c b/printk.c
> index ae28c4f..51b618e 100644
> --- a/printk.c
> +++ b/printk.c
> @@ -221,7 +221,7 @@ dump_record(struct prb_map *m, unsigned long id, int
msg_flags)
> char *p1 = strstr(buf, "_R");
> if (!p1)
> p1 = strstr(buf, "_ZN");
> - char *p2 = strchrnul(buf, '+');
> + char *p2 = strrchr(buf, '+');
> if (p1 && p2) {
> char mangled[BUFSIZE] = {0};
> char demangled[BUFSIZE] = {0};
>
> I did not reproduce it, but I guess that this should be related to the
strchrnul(), let's replace it with the strrchr().
>
> Thanks.
> Lianbo
>
>
> Thanks.
> Lianbo
>
>
> $ diff -u log.pre log.cur
> --- log.pre 2025-09-16 13:14:31.022206514 +0900
> +++ log.cur 2025-09-16 13:14:56.220390987 +0900
> @@ -210,7 +210,7 @@
> [ 0.169375] clocksource: jiffies: mask: 0xffffffff
max_cycles: 0xffffffff, max_idle_ns: 1911260446275000 ns
> [ 0.169375] futex hash table entries: 1024 (order: 4,
65536 bytes, linear)
> [ 0.169375] pinctrl core: initialized pinctrl subsystem
> -[ 0.172925] NET: Registered PF_NETLINK/PF_ROUTE protocol
family
> +[ 0.172925]
> [ 0.172983] DMA: preallocated 512 KiB GFP_KERNEL pool for
atomic allocations
> [ 0.172986] DMA: preallocated 512 KiB GFP_KERNEL|GFP_DMA
pool for atomic allocations
> [ 0.172988] DMA: preallocated 512 KiB GFP_KERNEL|GFP_DMA32
pool for atomic allocations
> @@ -807,7 +807,7 @@
> [771438.513231] entry_SYSCALL_64_after_hwframe+0x72/0xdc
> [771438.513423] RIP: 0033:0x7fbd9f8fda57
> [771438.513576] Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff
ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00
00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89
74 24
> -[771438.514251] RSP: 002b:00007ffee0de2b98 EFLAGS: 00000246
ORIG_RAX: 0000000000000001
> +[771438.514251]
> [771438.514534] RAX: ffffffffffffffda RBX: 0000000000000002
RCX: 00007fbd9f8fda57
> [771438.514800] RDX: 0000000000000002 RSI: 00005647ccc0a330
RDI: 0000000000000001
> [771438.515066] RBP: 00005647ccc0a330 R08: 0000000000000003
R09: 0000000000000000
>
> log.cur: 99bb57ac98afd89fcf23f0c8bc637821dcbd278f
> log.pre: a5942e3acfd9330d101cc65ef2e19e627233ddf6
> vmcore: panic by sysrq-trigger on 5.14.0-427.13.1.el9_4.x86_64
> (found also on 6.17-rc6)
>
> Thanks,
> Kazu
>
> On 2025/09/15 10:19, Tao Liu wrote:
> > applied:
https://github.com/crash-utility/crash/commit/99bb57ac98afd89fcf23f0c8bc6...
<
https://github.com/crash-utility/crash/commit/99bb57ac98afd89fcf23f0c8bc6...
>
> >
> > On Wed, Sep 10, 2025 at 2:33 PM Tao Liu <ltao(a)redhat.com
<mailto:ltao@redhat.com>> wrote:
> >>
> >> Hi lianbo,
> >>
> >> Thanks for the v2, LGTM, ack.
> >>
> >>
> >> On Mon, Sep 8, 2025 at 8:42 PM Lianbo Jiang <
lijiang(a)redhat.com <mailto:lijiang@redhat.com>> wrote:
> >>>
> >>> Without the patch:
> >>> crash> log
> >>> ...
> >>> [ 2174.308966] Call Trace:
> >>> [ 2174.311693] <TASK>
> >>> [ 2174.314033] dump_stack_lvl+0x5d/0x80
> >>> [ 2174.318125] panic+0x156/0x32a
> >>> [ 2174.321539]
_RNvCscb18lrEyTSA_10rust_panic10area_in_hp+0xf7/0x120 [rust_panic]
> >>> [ 2174.329700] ? console_unlock+0x9c/0x140
> >>> [ 2174.334080] ? irq_work_queue+0x2d/0x50
> >>> [ 2174.338352] ? __pfx_init_module+0x10/0x10
[rust_panic]
> >>> [ 2174.344183]
_RNvMCscb18lrEyTSA_10rust_panicNtB2_10HelloPanic8step_two+0x20/0xe0
[rust_panic]
> >>> [ 2174.353698] ? _printk+0x6b/0x90
> >>> ...
> >>>
> >>> With the patch:
> >>> crash> log
> >>> ...
> >>> [ 2174.308966] Call Trace:
> >>> [ 2174.311693] <TASK>
> >>> [ 2174.314033] dump_stack_lvl+0x5d/0x80
> >>> [ 2174.318125] panic+0x156/0x32a
> >>> [ 2174.321539] rust_panic::area_in_hp+0xf7/0x120
[rust_panic]
> >>> [ 2174.329700] ? console_unlock+0x9c/0x140
> >>> [ 2174.334080] ? irq_work_queue+0x2d/0x50
> >>> [ 2174.338352] ? __pfx_init_module+0x10/0x10
[rust_panic]
> >>> [ 2174.344183]
<rust_panic::HelloPanic>::step_two+0x20/0xe0 [rust_panic]
> >>> [ 2174.353698] ? _printk+0x6b/0x90
> >>> ...
> >>>
> >>> Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com
<mailto:
lijiang(a)redhat.com>>
> >>> ---
> >>> Note:
> >>> 1. Add some checks to avoid the risk of buffer overflow.
> >>>
> >>> Makefile | 2 +-
> >>> printk.c | 33 ++++++++++++++++++++++++++++++++-
> >>> 2 files changed, 33 insertions(+), 2 deletions(-)
> >>>
> >>> diff --git a/Makefile b/Makefile
> >>> index fc1c9588dcfa..b277129f6df2 100644
> >>> --- a/Makefile
> >>> +++ b/Makefile
> >>> @@ -421,7 +421,7 @@ kernel.o: ${GENERIC_HFILES} kernel.c
> >>> ${CC} -c ${CRASH_CFLAGS} kernel.c
-I${BFD_DIRECTORY} -I${GDB_INCLUDE_DIRECTORY} ${WARNING_OPTIONS}
${WARNING_ERROR}
> >>>
> >>> printk.o: ${GENERIC_HFILES} printk.c
> >>> - ${CC} -c ${CRASH_CFLAGS} printk.c
${WARNING_OPTIONS} ${WARNING_ERROR}
> >>> + ${CC} -c ${CRASH_CFLAGS} printk.c
-I${GDB_INCLUDE_DIRECTORY} ${WARNING_OPTIONS} ${WARNING_ERROR}
> >>>
> >>> gdb_interface.o: ${GENERIC_HFILES} gdb_interface.c
> >>> ${CC} -c ${CRASH_CFLAGS} gdb_interface.c
${WARNING_OPTIONS} ${WARNING_ERROR}
> >>> diff --git a/printk.c b/printk.c
> >>> index 95db7e607e4c..ae28c4fa0b21 100644
> >>> --- a/printk.c
> >>> +++ b/printk.c
> >>> @@ -1,5 +1,6 @@
> >>> #include "defs.h"
> >>> #include <ctype.h>
> >>> +#include "demangle.h"
> >>>
> >>> /* convenience struct for passing many values to helper
functions */
> >>> struct prb_map {
> >>> @@ -201,14 +202,44 @@ dump_record(struct prb_map *m,
unsigned long id, int msg_flags)
> >>>
> >>> text = m->text_data + begin;
> >>>
> >>> + if (text_len > BUFSIZE) {
> >>> + error(WARNING, "\nThe messages could be
truncated!\n");
> >>> + text_len = BUFSIZE;
> >>> + }
> >>> +
> >>> for (i = 0, p = text; i < text_len; i++, p++) {
> >>> if (*p == '\n')
> >>> fprintf(fp, "\n%s",
space(ilen));
> >>> else if (isprint(*p) || isspace(*p))
> >>> - fputc(*p, fp);
> >>> + sprintf(&buf[i], "%c",
*p);
> >>> else
> >>> fputc('.', fp);
> >>> }
> >>> + /*
> >>> + * Try to demangle a mangled Rust symbol(calltrace)
from log buffer
> >>> + */
> >>> + char *p1 = strstr(buf, "_R");
> >>> + if (!p1)
> >>> + p1 = strstr(buf, "_ZN");
> >>> + char *p2 = strchrnul(buf, '+');
> >>> + if (p1 && p2) {
> >>> + char mangled[BUFSIZE] = {0};
> >>> + char demangled[BUFSIZE] = {0};
> >>> + char *res;
> >>> + size_t slen = p1 - buf;
> >>> +
> >>> + if (slen)
> >>> + memcpy(demangled, buf, slen);
> >>> +
> >>> + memcpy(mangled, p1, p2-p1);
> >>> + res = rust_demangle(mangled, DMGL_RUST);
> >>> + if (res) {
> >>> + snprintf(demangled+slen,
BUFSIZE-slen, "%s%s", res, p2);
> >>> + fprintf(fp,
"%s",demangled);
> >>> + free(res);
> >>> + }
> >>> + } else
> >>> + fprintf(fp, "%s", buf);
> >>>
> >>> if (msg_flags & SHOW_LOG_DICT) {
> >>> text = info + OFFSET(printk_info_dev_info)
+
> >>> --
> >>> 2.50.1
> >>>
> > --
> > Crash-utility mailing list --
devel(a)lists.crash-utility.osci.io <mailto:
devel(a)lists.crash-utility.osci.io>
> > To unsubscribe send an email to
devel-leave(a)lists.crash-utility.osci.io <mailto:
devel-leave(a)lists.crash-utility.osci.io>
> > https://${domain_name}/admin/lists/
devel.lists.crash-utility.osci.io/ <
http://devel.lists.crash-utility.osci.io/>
> > Contribution Guidelines:
https://github.com/crash-utility/crash/wiki <
https://github.com/crash-utility/crash/wiki>
>
1:18 p.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
Hi Lianbo,
It seems we have a problem printing disassembly blocks in the log after this patch (at
least on s390).
See number of empty lines printed below.
Before the patch:
[ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00 0000000015800000
0000000000001000
[ 21.408787] 0000000008e30000 00000000b0001000 0000000000000000
0000000000000a55
[ 21.408790] 0000000004c52300 000002aa3780c000 00000000084281d0
0000038000bfbd28
[ 21.408794] 00000000075e9500 0000000004c52300 0000038000bfbbf0
0000038000bfbb90
[ 21.408860] Krnl Code: 000000000e0acf48: c05fb0001000 llilf %r5,2952794112
000000000e0acf4e: ec4100b30659 risbgn %r4,%r1,0,179,6
#000000000e0acf54: 0e24 mvcl %r2,%r4
000000000e0acf56: a7280000 lhi %r2,0
000000000e0acf5a: eb6ff0a80004 lmg %r6,%r15,168(%r15)
000000000e0acf60: b9140022 lgfr %r2,%r2
000000000e0acf64: 07fe bcr 15,%r14
000000000e0acf66: 47000700 bc 0,1792
[ 21.408883] Call Trace:
After the patch:
[ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00 0000000015800000
0000000000001000
[ 21.408787] 0000000008e30000 00000000b0001000 0000000000000000
0000000000000a55
[ 21.408790] 0000000004c52300 000002aa3780c000 00000000084281d0
0000038000bfbd28
[ 21.408794] 00000000075e9500 0000000004c52300 0000038000bfbbf0
0000038000bfbb90
[ 21.408860]
Krnl Code: 000000000e0acf48: c05fb0001000 llilf %r5,2952794112
[ 21.408883] Call Trace:
I think your approach of storing printable characters in the buffer with the intention to
modify it
afterwards (see [1] below) instead of writing it character wise does not work when the
input data
contains several lines. Those '\n' are written one by one, what leads to the
result shown above.
You should probably buffer and 'demangle' each line separately.
On 9/8/2025 10:42 AM, Lianbo Jiang wrote:
Without the patch:
crash> log
...
[ 2174.308966] Call Trace:
[ 2174.311693] <TASK>
[ 2174.314033] dump_stack_lvl+0x5d/0x80
[ 2174.318125] panic+0x156/0x32a
[ 2174.321539] _RNvCscb18lrEyTSA_10rust_panic10area_in_hp+0xf7/0x120 [rust_panic]
[ 2174.329700] ? console_unlock+0x9c/0x140
[ 2174.334080] ? irq_work_queue+0x2d/0x50
[ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
[ 2174.344183] _RNvMCscb18lrEyTSA_10rust_panicNtB2_10HelloPanic8step_two+0x20/0xe0
[rust_panic]
[ 2174.353698] ? _printk+0x6b/0x90
...
With the patch:
crash> log
...
[ 2174.308966] Call Trace:
[ 2174.311693] <TASK>
[ 2174.314033] dump_stack_lvl+0x5d/0x80
[ 2174.318125] panic+0x156/0x32a
[ 2174.321539] rust_panic::area_in_hp+0xf7/0x120 [rust_panic]
[ 2174.329700] ? console_unlock+0x9c/0x140
[ 2174.334080] ? irq_work_queue+0x2d/0x50
[ 2174.338352] ? __pfx_init_module+0x10/0x10 [rust_panic]
[ 2174.344183] <rust_panic::HelloPanic>::step_two+0x20/0xe0 [rust_panic]
[ 2174.353698] ? _printk+0x6b/0x90
...
Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com>
---
index 95db7e607e4c..ae28c4fa0b21 100644
--- a/printk.c
+++ b/printk.c
@@ -1,5 +1,6 @@
#include "defs.h"
#include <ctype.h>
+#include "demangle.h"
/* convenience struct for passing many values to helper functions */
struct prb_map {
@@ -201,14 +202,44 @@ dump_record(struct prb_map *m, unsigned long id, int msg_flags)
text = m->text_data + begin;
+ if (text_len > BUFSIZE) {
+ error(WARNING, "\nThe messages could be truncated!\n");
+ text_len = BUFSIZE;
+ }
+
for (i = 0, p = text; i < text_len; i++, p++) {
if (*p == '\n')
fprintf(fp, "\n%s", space(ilen));
else if (isprint(*p) || isspace(*p))
- fputc(*p, fp);
+ sprintf(&buf[i], "%c", *p);
[1]
else
fputc('.', fp);
}
+ /*
+ * Try to demangle a mangled Rust symbol(calltrace) from log buffer
+ */
+ char *p1 = strstr(buf, "_R");
+ if (!p1)
+ p1 = strstr(buf, "_ZN");
+ char *p2 = strchrnul(buf, '+');
+ if (p1 && p2) {
+ char mangled[BUFSIZE] = {0};
+ char demangled[BUFSIZE] = {0};
+ char *res;
+ size_t slen = p1 - buf;
+
+ if (slen)
+ memcpy(demangled, buf, slen);
+
+ memcpy(mangled, p1, p2-p1);
+ res = rust_demangle(mangled, DMGL_RUST);
+ if (res) {
+ snprintf(demangled+slen, BUFSIZE-slen, "%s%s", res, p2);
+ fprintf(fp, "%s",demangled);
+ free(res);
+ }
+ } else
+ fprintf(fp, "%s", buf);
if (msg_flags & SHOW_LOG_DICT) {
text = info + OFFSET(printk_info_dev_info) +
Thanks,
Mikhail
9:53 p.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
On Tue, Sep 30, 2025 at 2:18 AM Mikhail Zaslonko <zaslonko(a)linux.ibm.com>
wrote:
Hi Lianbo,
It seems we have a problem printing disassembly blocks in the log after
this patch (at least on s390).
See number of empty lines printed below.
Can you try it with the following two patches?
[1]
https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01621.html
[2]
https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01636.html
Before the patch:
[ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
0000000015800000 0000000000001000
[ 21.408787] 0000000008e30000 00000000b0001000
0000000000000000 0000000000000a55
[ 21.408790] 0000000004c52300 000002aa3780c000
00000000084281d0 0000038000bfbd28
[ 21.408794] 00000000075e9500 0000000004c52300
0000038000bfbbf0 0000038000bfbb90
[ 21.408860] Krnl Code: 000000000e0acf48: c05fb0001000 llilf
%r5,2952794112
000000000e0acf4e: ec4100b30659 risbgn
%r4,%r1,0,179,6
#000000000e0acf54: 0e24 mvcl
%r2,%r4
>000000000e0acf56: a7280000 lhi
%r2,0
000000000e0acf5a: eb6ff0a80004 lmg
%r6,%r15,168(%r15)
000000000e0acf60: b9140022 lgfr
%r2,%r2
000000000e0acf64: 07fe bcr
15,%r14
000000000e0acf66: 47000700 bc
0,1792
[ 21.408883] Call Trace:
After the patch:
[ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
0000000015800000 0000000000001000
[ 21.408787] 0000000008e30000 00000000b0001000
0000000000000000 0000000000000a55
[ 21.408790] 0000000004c52300 000002aa3780c000
00000000084281d0 0000038000bfbd28
[ 21.408794] 00000000075e9500 0000000004c52300
0000038000bfbbf0 0000038000bfbb90
[ 21.408860]
Krnl Code: 000000000e0acf48: c05fb0001000 llilf
%r5,2952794112
[ 21.408883] Call Trace:
I think your approach of storing printable characters in the buffer with
the intention to modify it
afterwards (see [1] below) instead of writing it character wise does not
work when the input data
contains several lines. Those '\n' are written one by one, what leads to
the result shown above.
You should probably buffer and 'demangle' each line separately.
Looks like different issues. Can you share your vmcore and vmlinux with
me? I did not reproduce it.
Thanks
Lianbo
2:01 a.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
Hello,
On 9/30/2025 4:53 AM, lijiang wrote:
On Tue, Sep 30, 2025 at 2:18 AM Mikhail Zaslonko
<zaslonko(a)linux.ibm.com>
wrote:
> Hi Lianbo,
>
> It seems we have a problem printing disassembly blocks in the log after
> this patch (at least on s390).
> See number of empty lines printed below.
>
Can you try it with the following two patches?
[1]
https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01621.html
This
patch is present on crash master, doesnt affect the issue.
This one helps indeed! At least I do not se the blanks lines in my scenario.
BUT, if I use 'log -R' the blank lines are back again!
> Before the patch:
> [ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
> 0000000015800000 0000000000001000
> [ 21.408787] 0000000008e30000 00000000b0001000
> 0000000000000000 0000000000000a55
> [ 21.408790] 0000000004c52300 000002aa3780c000
> 00000000084281d0 0000038000bfbd28
> [ 21.408794] 00000000075e9500 0000000004c52300
> 0000038000bfbbf0 0000038000bfbb90
> [ 21.408860] Krnl Code: 000000000e0acf48: c05fb0001000 llilf
> %r5,2952794112
> 000000000e0acf4e: ec4100b30659 risbgn
> %r4,%r1,0,179,6
> #000000000e0acf54: 0e24 mvcl
> %r2,%r4
> >000000000e0acf56: a7280000 lhi
> %r2,0
> 000000000e0acf5a: eb6ff0a80004 lmg
> %r6,%r15,168(%r15)
> 000000000e0acf60: b9140022 lgfr
> %r2,%r2
> 000000000e0acf64: 07fe bcr
> 15,%r14
> 000000000e0acf66: 47000700 bc
> 0,1792
> [ 21.408883] Call Trace:
>
> After the patch:
> [ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
> 0000000015800000 0000000000001000
> [ 21.408787] 0000000008e30000 00000000b0001000
> 0000000000000000 0000000000000a55
> [ 21.408790] 0000000004c52300 000002aa3780c000
> 00000000084281d0 0000038000bfbd28
> [ 21.408794] 00000000075e9500 0000000004c52300
> 0000038000bfbbf0 0000038000bfbb90
> [ 21.408860]
>
>
>
>
>
>
> Krnl Code: 000000000e0acf48: c05fb0001000 llilf
> %r5,2952794112
> [ 21.408883] Call Trace:
>
> I think your approach of storing printable characters in the buffer with
> the intention to modify it
> afterwards (see [1] below) instead of writing it character wise does not
> work when the input data
> contains several lines. Those '\n' are written one by one, what leads to
> the result shown above.
> You should probably buffer and 'demangle' each line separately.
>
Looks like different issues. Can you share your vmcore and vmlinux with
me? I did not reproduce it.
Thanks
Lianbo
>
>
2:18 a.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
On Tue, Sep 30, 2025 at 3:01 PM Mikhail Zaslonko <zaslonko(a)linux.ibm.com>
wrote:
Hello,
On 9/30/2025 4:53 AM, lijiang wrote:
> On Tue, Sep 30, 2025 at 2:18 AM Mikhail Zaslonko <zaslonko(a)linux.ibm.com
>
> wrote:
>
>> Hi Lianbo,
>>
>> It seems we have a problem printing disassembly blocks in the log after
>> this patch (at least on s390).
>> See number of empty lines printed below.
>>
>
> Can you try it with the following two patches?
> [1]
>
https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01621.html
This patch is present on crash master, doesnt affect the issue.
> [2]
>
https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01636.html
>
This one helps indeed! At least I do not se the blanks lines in my
scenario.
BUT, if I use 'log -R' the blank lines are back again!
Thanks for the information, Mikhail.
Let me see how to debug this(although I can not reproduce it on s390x).
Thanks
Lianbo
>
>> Before the patch:
>> [ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
>> 0000000015800000 0000000000001000
>> [ 21.408787] 0000000008e30000 00000000b0001000
>> 0000000000000000 0000000000000a55
>> [ 21.408790] 0000000004c52300 000002aa3780c000
>> 00000000084281d0 0000038000bfbd28
>> [ 21.408794] 00000000075e9500 0000000004c52300
>> 0000038000bfbbf0 0000038000bfbb90
>> [ 21.408860] Krnl Code: 000000000e0acf48: c05fb0001000 llilf
>> %r5,2952794112
>> 000000000e0acf4e: ec4100b30659 risbgn
>> %r4,%r1,0,179,6
>> #000000000e0acf54: 0e24 mvcl
>> %r2,%r4
>> >000000000e0acf56: a7280000 lhi
>> %r2,0
>> 000000000e0acf5a: eb6ff0a80004 lmg
>> %r6,%r15,168(%r15)
>> 000000000e0acf60: b9140022 lgfr
>> %r2,%r2
>> 000000000e0acf64: 07fe bcr
>> 15,%r14
>> 000000000e0acf66: 47000700 bc
>> 0,1792
>> [ 21.408883] Call Trace:
>>
>> After the patch:
>> [ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
>> 0000000015800000 0000000000001000
>> [ 21.408787] 0000000008e30000 00000000b0001000
>> 0000000000000000 0000000000000a55
>> [ 21.408790] 0000000004c52300 000002aa3780c000
>> 00000000084281d0 0000038000bfbd28
>> [ 21.408794] 00000000075e9500 0000000004c52300
>> 0000038000bfbbf0 0000038000bfbb90
>> [ 21.408860]
>>
>>
>>
>>
>>
>>
>> Krnl Code: 000000000e0acf48: c05fb0001000 llilf
>> %r5,2952794112
>> [ 21.408883] Call Trace:
>>
>> I think your approach of storing printable characters in the buffer with
>> the intention to modify it
>> afterwards (see [1] below) instead of writing it character wise does not
>> work when the input data
>> contains several lines. Those '\n' are written one by one, what leads
to
>> the result shown above.
>> You should probably buffer and 'demangle' each line separately.
>>
>
> Looks like different issues. Can you share your vmcore and vmlinux with
> me? I did not reproduce it.
>
> Thanks
> Lianbo
>
>>
>>
>
6:11 p.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
On Tue, Sep 30, 2025 at 8:18 PM lijiang <lijiang(a)redhat.com> wrote:
On Tue, Sep 30, 2025 at 3:01 PM Mikhail Zaslonko <zaslonko(a)linux.ibm.com> wrote:
>
> Hello,
>
> On 9/30/2025 4:53 AM, lijiang wrote:
> > On Tue, Sep 30, 2025 at 2:18 AM Mikhail Zaslonko <zaslonko(a)linux.ibm.com>
> > wrote:
> >
> >> Hi Lianbo,
> >>
> >> It seems we have a problem printing disassembly blocks in the log after
> >> this patch (at least on s390).
> >> See number of empty lines printed below.
> >>
> >
> > Can you try it with the following two patches?
> > [1]
> > https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01621.html
> This patch is present on crash master, doesnt affect the issue.
> > [2]
> > https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01636.html
> >
> This one helps indeed! At least I do not se the blanks lines in my scenario.
> BUT, if I use 'log -R' the blank lines are back again!
Thanks for the information, Mikhail.
Let me see how to debug this(although I can not reproduce it on s390x).
I didn't reproduce the issue on my s390x machine either, maybe sharing
the vmcore to us can help.
Thanks,
Tao Liu
Thanks
Lianbo
>
>
> >
> >> Before the patch:
> >> [ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
> >> 0000000015800000 0000000000001000
> >> [ 21.408787] 0000000008e30000 00000000b0001000
> >> 0000000000000000 0000000000000a55
> >> [ 21.408790] 0000000004c52300 000002aa3780c000
> >> 00000000084281d0 0000038000bfbd28
> >> [ 21.408794] 00000000075e9500 0000000004c52300
> >> 0000038000bfbbf0 0000038000bfbb90
> >> [ 21.408860] Krnl Code: 000000000e0acf48: c05fb0001000 llilf
> >> %r5,2952794112
> >> 000000000e0acf4e: ec4100b30659 risbgn
> >> %r4,%r1,0,179,6
> >> #000000000e0acf54: 0e24 mvcl
> >> %r2,%r4
> >> >000000000e0acf56: a7280000 lhi
> >> %r2,0
> >> 000000000e0acf5a: eb6ff0a80004 lmg
> >> %r6,%r15,168(%r15)
> >> 000000000e0acf60: b9140022 lgfr
> >> %r2,%r2
> >> 000000000e0acf64: 07fe bcr
> >> 15,%r14
> >> 000000000e0acf66: 47000700 bc
> >> 0,1792
> >> [ 21.408883] Call Trace:
> >>
> >> After the patch:
> >> [ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
> >> 0000000015800000 0000000000001000
> >> [ 21.408787] 0000000008e30000 00000000b0001000
> >> 0000000000000000 0000000000000a55
> >> [ 21.408790] 0000000004c52300 000002aa3780c000
> >> 00000000084281d0 0000038000bfbd28
> >> [ 21.408794] 00000000075e9500 0000000004c52300
> >> 0000038000bfbbf0 0000038000bfbb90
> >> [ 21.408860]
> >>
> >>
> >>
> >>
> >>
> >>
> >> Krnl Code: 000000000e0acf48: c05fb0001000 llilf
> >> %r5,2952794112
> >> [ 21.408883] Call Trace:
> >>
> >> I think your approach of storing printable characters in the buffer with
> >> the intention to modify it
> >> afterwards (see [1] below) instead of writing it character wise does not
> >> work when the input data
> >> contains several lines. Those '\n' are written one by one, what
leads to
> >> the result shown above.
> >> You should probably buffer and 'demangle' each line separately.
> >>
> >
> > Looks like different issues. Can you share your vmcore and vmlinux with
> > me? I did not reproduce it.
>
>
> >
> > Thanks
> > Lianbo
> >
> >>
> >>
> >
>
6:36 a.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
Hi Tao,
On 10/7/2025 1:11 AM, Tao Liu wrote:
On Tue, Sep 30, 2025 at 8:18 PM lijiang <lijiang(a)redhat.com>
wrote:
>
> On Tue, Sep 30, 2025 at 3:01 PM Mikhail Zaslonko <zaslonko(a)linux.ibm.com>
wrote:
>>
>> Hello,
>>
>> On 9/30/2025 4:53 AM, lijiang wrote:
>>> On Tue, Sep 30, 2025 at 2:18 AM Mikhail Zaslonko
<zaslonko(a)linux.ibm.com>
>>> wrote:
>>>
>>>> Hi Lianbo,
>>>>
>>>> It seems we have a problem printing disassembly blocks in the log after
>>>> this patch (at least on s390).
>>>> See number of empty lines printed below.
>>>>
>>>
>>> Can you try it with the following two patches?
>>> [1]
>>> https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01621.html
>> This patch is present on crash master, doesnt affect the issue.
>>> [2]
>>> https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01636.html
>>>
>> This one helps indeed! At least I do not se the blanks lines in my scenario.
>> BUT, if I use 'log -R' the blank lines are back again!
>
>
> Thanks for the information, Mikhail.
> Let me see how to debug this(although I can not reproduce it on s390x).
I didn't reproduce the issue on my s390x machine either, maybe sharing
the vmcore to us can help.
I'm not sure I'm allowed to send this data outside.
I think the problem takes place for the logs printed with pr_cont() by the
kernel (e.g. show_code() of arch/s390/kernel/dis.c for printing disassembly as
in my sample).
Thanks,
Tao Liu
>
> Thanks
> Lianbo
>
>>
>>
>>>
>>>> Before the patch:
>>>> [ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
>>>> 0000000015800000 0000000000001000
>>>> [ 21.408787] 0000000008e30000 00000000b0001000
>>>> 0000000000000000 0000000000000a55
>>>> [ 21.408790] 0000000004c52300 000002aa3780c000
>>>> 00000000084281d0 0000038000bfbd28
>>>> [ 21.408794] 00000000075e9500 0000000004c52300
>>>> 0000038000bfbbf0 0000038000bfbb90
>>>> [ 21.408860] Krnl Code: 000000000e0acf48: c05fb0001000 llilf
>>>> %r5,2952794112
>>>> 000000000e0acf4e: ec4100b30659 risbgn
>>>> %r4,%r1,0,179,6
>>>> #000000000e0acf54: 0e24 mvcl
>>>> %r2,%r4
>>>> >000000000e0acf56: a7280000 lhi
>>>> %r2,0
>>>> 000000000e0acf5a: eb6ff0a80004 lmg
>>>> %r6,%r15,168(%r15)
>>>> 000000000e0acf60: b9140022 lgfr
>>>> %r2,%r2
>>>> 000000000e0acf64: 07fe bcr
>>>> 15,%r14
>>>> 000000000e0acf66: 47000700 bc
>>>> 0,1792
>>>> [ 21.408883] Call Trace:
>>>>
>>>> After the patch:
>>>> [ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
>>>> 0000000015800000 0000000000001000
>>>> [ 21.408787] 0000000008e30000 00000000b0001000
>>>> 0000000000000000 0000000000000a55
>>>> [ 21.408790] 0000000004c52300 000002aa3780c000
>>>> 00000000084281d0 0000038000bfbd28
>>>> [ 21.408794] 00000000075e9500 0000000004c52300
>>>> 0000038000bfbbf0 0000038000bfbb90
>>>> [ 21.408860]
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> Krnl Code: 000000000e0acf48: c05fb0001000 llilf
>>>> %r5,2952794112
>>>> [ 21.408883] Call Trace:
>>>>
>>>> I think your approach of storing printable characters in the buffer with
>>>> the intention to modify it
>>>> afterwards (see [1] below) instead of writing it character wise does not
>>>> work when the input data
>>>> contains several lines. Those '\n' are written one by one, what
leads to
>>>> the result shown above.
>>>> You should probably buffer and 'demangle' each line separately.
>>>>
>>>
>>> Looks like different issues. Can you share your vmcore and vmlinux with
>>> me? I did not reproduce it.
>>
>>
>>>
>>> Thanks
>>> Lianbo
>>>
>>>>
>>>>
>>>
>>
4:55 a.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
Hello Tao,
Have you reproduced the issue on s390?
Just trigger a segfault in the test program (e.g. by de-referencing a
null pointer), run crash on a live system and check the 'log' output.
On 10/7/2025 1:36 PM, Mikhail Zaslonko wrote:
Hi Tao,
On 10/7/2025 1:11 AM, Tao Liu wrote:
> On Tue, Sep 30, 2025 at 8:18 PM lijiang <lijiang(a)redhat.com> wrote:
>>
>> On Tue, Sep 30, 2025 at 3:01 PM Mikhail Zaslonko <zaslonko(a)linux.ibm.com>
wrote:
>>>
>>> Hello,
>>>
>>> On 9/30/2025 4:53 AM, lijiang wrote:
>>>> On Tue, Sep 30, 2025 at 2:18 AM Mikhail Zaslonko
<zaslonko(a)linux.ibm.com>
>>>> wrote:
>>>>
>>>>> Hi Lianbo,
>>>>>
>>>>> It seems we have a problem printing disassembly blocks in the log
after
>>>>> this patch (at least on s390).
>>>>> See number of empty lines printed below.
>>>>>
>>>>
>>>> Can you try it with the following two patches?
>>>> [1]
>>>>
https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01621.html
>>> This patch is present on crash master, doesnt affect the issue.
>>>> [2]
>>>>
https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01636.html
>>>>
>>> This one helps indeed! At least I do not se the blanks lines in my scenario.
>>> BUT, if I use 'log -R' the blank lines are back again!
>>
>>
>> Thanks for the information, Mikhail.
>> Let me see how to debug this(although I can not reproduce it on s390x).
>
> I didn't reproduce the issue on my s390x machine either, maybe sharing
> the vmcore to us can help.
I'm not sure I'm allowed to send this data outside.
I think the problem takes place for the logs printed with pr_cont() by the
kernel (e.g. show_code() of arch/s390/kernel/dis.c for printing disassembly as
in my sample).
>
> Thanks,
> Tao Liu
>
>>
>> Thanks
>> Lianbo
>>
>>>
>>>
>>>>
>>>>> Before the patch:
>>>>> [ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
>>>>> 0000000015800000 0000000000001000
>>>>> [ 21.408787] 0000000008e30000 00000000b0001000
>>>>> 0000000000000000 0000000000000a55
>>>>> [ 21.408790] 0000000004c52300 000002aa3780c000
>>>>> 00000000084281d0 0000038000bfbd28
>>>>> [ 21.408794] 00000000075e9500 0000000004c52300
>>>>> 0000038000bfbbf0 0000038000bfbb90
>>>>> [ 21.408860] Krnl Code: 000000000e0acf48: c05fb0001000
llilf
>>>>> %r5,2952794112
>>>>> 000000000e0acf4e: ec4100b30659
risbgn
>>>>> %r4,%r1,0,179,6
>>>>> #000000000e0acf54: 0e24
mvcl
>>>>> %r2,%r4
>>>>> >000000000e0acf56: a7280000
lhi
>>>>> %r2,0
>>>>> 000000000e0acf5a: eb6ff0a80004
lmg
>>>>> %r6,%r15,168(%r15)
>>>>> 000000000e0acf60: b9140022
lgfr
>>>>> %r2,%r2
>>>>> 000000000e0acf64: 07fe
bcr
>>>>> 15,%r14
>>>>> 000000000e0acf66: 47000700 bc
>>>>> 0,1792
>>>>> [ 21.408883] Call Trace:
>>>>>
>>>>> After the patch:
>>>>> [ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
>>>>> 0000000015800000 0000000000001000
>>>>> [ 21.408787] 0000000008e30000 00000000b0001000
>>>>> 0000000000000000 0000000000000a55
>>>>> [ 21.408790] 0000000004c52300 000002aa3780c000
>>>>> 00000000084281d0 0000038000bfbd28
>>>>> [ 21.408794] 00000000075e9500 0000000004c52300
>>>>> 0000038000bfbbf0 0000038000bfbb90
>>>>> [ 21.408860]
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> Krnl Code: 000000000e0acf48: c05fb0001000
llilf
>>>>> %r5,2952794112
>>>>> [ 21.408883] Call Trace:
>>>>>
>>>>> I think your approach of storing printable characters in the buffer
with
>>>>> the intention to modify it
>>>>> afterwards (see [1] below) instead of writing it character wise does
not
>>>>> work when the input data
>>>>> contains several lines. Those '\n' are written one by one,
what leads to
>>>>> the result shown above.
>>>>> You should probably buffer and 'demangle' each line
separately.
>>>>>
>>>>
>>>> Looks like different issues. Can you share your vmcore and vmlinux with
>>>> me? I did not reproduce it.
>>>
>>>
>>>>
>>>> Thanks
>>>> Lianbo
>>>>
>>>>>
>>>>>
>>>>
>>>
>
3:32 p.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
Hi Mikhail,
On Fri, Oct 10, 2025 at 10:55 PM Mikhail Zaslonko
<zaslonko(a)linux.ibm.com> wrote:
Hello Tao,
Have you reproduced the issue on s390?
Just trigger a segfault in the test program (e.g. by de-referencing a
null pointer), run crash on a live system and check the 'log' output.
Thanks for the suggestion. I will give null pointer dereferencing a
try and post findings.
Thanks,
Tao Liu
On 10/7/2025 1:36 PM, Mikhail Zaslonko wrote:
> Hi Tao,
>
> On 10/7/2025 1:11 AM, Tao Liu wrote:
>> On Tue, Sep 30, 2025 at 8:18 PM lijiang <lijiang(a)redhat.com> wrote:
>>>
>>> On Tue, Sep 30, 2025 at 3:01 PM Mikhail Zaslonko
<zaslonko(a)linux.ibm.com> wrote:
>>>>
>>>> Hello,
>>>>
>>>> On 9/30/2025 4:53 AM, lijiang wrote:
>>>>> On Tue, Sep 30, 2025 at 2:18 AM Mikhail Zaslonko
<zaslonko(a)linux.ibm.com>
>>>>> wrote:
>>>>>
>>>>>> Hi Lianbo,
>>>>>>
>>>>>> It seems we have a problem printing disassembly blocks in the
log after
>>>>>> this patch (at least on s390).
>>>>>> See number of empty lines printed below.
>>>>>>
>>>>>
>>>>> Can you try it with the following two patches?
>>>>> [1]
>>>>>
https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01621.html
>>>> This patch is present on crash master, doesnt affect the issue.
>>>>> [2]
>>>>>
https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01636.html
>>>>>
>>>> This one helps indeed! At least I do not se the blanks lines in my
scenario.
>>>> BUT, if I use 'log -R' the blank lines are back again!
>>>
>>>
>>> Thanks for the information, Mikhail.
>>> Let me see how to debug this(although I can not reproduce it on s390x).
>>
>> I didn't reproduce the issue on my s390x machine either, maybe sharing
>> the vmcore to us can help.
>
> I'm not sure I'm allowed to send this data outside.
>
> I think the problem takes place for the logs printed with pr_cont() by the
> kernel (e.g. show_code() of arch/s390/kernel/dis.c for printing disassembly as
> in my sample).
>
>>
>> Thanks,
>> Tao Liu
>>
>>>
>>> Thanks
>>> Lianbo
>>>
>>>>
>>>>
>>>>>
>>>>>> Before the patch:
>>>>>> [ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
>>>>>> 0000000015800000 0000000000001000
>>>>>> [ 21.408787] 0000000008e30000 00000000b0001000
>>>>>> 0000000000000000 0000000000000a55
>>>>>> [ 21.408790] 0000000004c52300 000002aa3780c000
>>>>>> 00000000084281d0 0000038000bfbd28
>>>>>> [ 21.408794] 00000000075e9500 0000000004c52300
>>>>>> 0000038000bfbbf0 0000038000bfbb90
>>>>>> [ 21.408860] Krnl Code: 000000000e0acf48: c05fb0001000
llilf
>>>>>> %r5,2952794112
>>>>>> 000000000e0acf4e: ec4100b30659
risbgn
>>>>>> %r4,%r1,0,179,6
>>>>>> #000000000e0acf54: 0e24
mvcl
>>>>>> %r2,%r4
>>>>>> >000000000e0acf56: a7280000
lhi
>>>>>> %r2,0
>>>>>> 000000000e0acf5a: eb6ff0a80004
lmg
>>>>>> %r6,%r15,168(%r15)
>>>>>> 000000000e0acf60: b9140022
lgfr
>>>>>> %r2,%r2
>>>>>> 000000000e0acf64: 07fe
bcr
>>>>>> 15,%r14
>>>>>> 000000000e0acf66: 47000700
bc
>>>>>> 0,1792
>>>>>> [ 21.408883] Call Trace:
>>>>>>
>>>>>> After the patch:
>>>>>> [ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
>>>>>> 0000000015800000 0000000000001000
>>>>>> [ 21.408787] 0000000008e30000 00000000b0001000
>>>>>> 0000000000000000 0000000000000a55
>>>>>> [ 21.408790] 0000000004c52300 000002aa3780c000
>>>>>> 00000000084281d0 0000038000bfbd28
>>>>>> [ 21.408794] 00000000075e9500 0000000004c52300
>>>>>> 0000038000bfbbf0 0000038000bfbb90
>>>>>> [ 21.408860]
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> Krnl Code: 000000000e0acf48: c05fb0001000
llilf
>>>>>> %r5,2952794112
>>>>>> [ 21.408883] Call Trace:
>>>>>>
>>>>>> I think your approach of storing printable characters in the
buffer with
>>>>>> the intention to modify it
>>>>>> afterwards (see [1] below) instead of writing it character wise
does not
>>>>>> work when the input data
>>>>>> contains several lines. Those '\n' are written one by
one, what leads to
>>>>>> the result shown above.
>>>>>> You should probably buffer and 'demangle' each line
separately.
>>>>>>
>>>>>
>>>>> Looks like different issues. Can you share your vmcore and vmlinux
with
>>>>> me? I did not reproduce it.
>>>>
>>>>
>>>>>
>>>>> Thanks
>>>>> Lianbo
>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>
>>
>
9:03 p.m.
New subject: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
On Tue, Oct 7, 2025 at 7:36 PM Mikhail Zaslonko <zaslonko(a)linux.ibm.com wrote:
Hi Tao,
On 10/7/2025 1:11 AM, Tao Liu wrote:
> On Tue, Sep 30, 2025 at 8:18 PM lijiang <lijiang(a)redhat.com> wrote:
> >> On Tue, Sep 30, 2025 at 3:01 PM Mikhail Zaslonko
<
zaslonko(a)linux.ibm.com> wrote:
>> >>> Hello,
>> >>> On 9/30/2025 4:53 AM,
lijiang wrote:
>>>> On Tue, Sep 30, 2025 at 2:18 AM Mikhail Zaslonko <
zaslonko(a)linux.ibm.com >>>> wrote:
>>> >>>>> Hi Lianbo,
>>>> >>>>> It seems we
have a problem printing disassembly blocks in the log
after
>>>>> this patch (at least on s390).
>>>>> See number of empty lines printed below.
>>>> >>> >>>> Can you try it with the following two
patches?
>>>> [1]
>>>
https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01621.html
>>> This patch is present on crash master, doesnt affect the issue.
>>>> [2]
>>>
https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01636.html
>>> >>> This one helps indeed!
At least I do not se the blanks lines in my
scenario.
>>> BUT, if I use 'log -R' the blank lines are back again!
> > >> Thanks for the
information, Mikhail.
>> Let me see how to debug this(although I can not reproduce it on s390x).
> I didn't reproduce the issue on my s390x machine
either, maybe sharing
> the vmcore to us can help.
I'm not sure I'm allowed to send this data outside.
Sorry for the late reply because of China holiday.
If you can share your test case(or steps), that will help me to reproduce
the current issue.
Anyway I will check it in detail.
I think the problem takes place for the logs printed with pr_cont() by the
kernel (e.g. show_code() of arch/s390/kernel/dis.c for printing
disassembly as
in my sample).
Thanks for the information.
Lianbo
174
days inactive
207
days old
devel@lists.crash-utility.osci.io
16 comments
5 participants
participants (5)
-
HAGIO KAZUHITO(萩尾 一仁) -
Lianbo Jiang -
lijiang
-
Mikhail Zaslonko -
Tao Liu