[BUG FIXED]fix bug of CACHED in kmem -i show memory
by 薛国伦
Hi lianbo:
I have a bug fixed need to merge to crash-utility which patch in attachment.
It can obviously see that kmem -i show memory info of system.
But CACHED have wrong output for add up size of cached memory.
The reason of this bug is:
newest kernel version use "struct address_space *swapper_spaces[MAX_SWAPFILES]"
instead of "struct address_space swapper_spaces[MAX_SWAPFILES]" in old kernel.
this change bring into kernel after kernel 4.11.0
So newest version need to readmem twice, first is address of one struct address_space
second is value of struct address_space.
This bug fix patch add twice readmem when read swapper_spaces struct, it can accurately
read nrpage in struct address_space. And i found that definition of struct address_space swapper_spaces
change in kernel 4.11.0, so i make kernel version compatible for this change.
fix before:
crash> kmem -i
PAGES TOTAL PERCENTAGE
TOTAL MEM 2854115 10.9 GB ----
FREE 169699 662.9 MB 5% of TOTAL MEM
USED 2684416 10.2 GB 94% of TOTAL MEM
SHARED 891094 3.4 GB 31% of TOTAL MEM
BUFFERS 329 1.3 MB 0% of TOTAL MEM
CACHED 873327085626 3331478.4 GB 30598875% of TOTAL MEM
SLAB 230128 898.9 MB 8% of TOTAL MEM
fix after:
crash> kmem -i
PAGES TOTAL PERCENTAGE
TOTAL MEM 2854115 10.9 GB ----
FREE 169699 662.9 MB 5% of TOTAL MEM
USED 2684416 10.2 GB 94% of TOTAL MEM
SHARED 891094 3.4 GB 31% of TOTAL MEM
BUFFERS 329 1.3 MB 0% of TOTAL MEM
CACHED 1729018 6.6 GB 60% of TOTAL MEM
SLAB 230128 898.9 MB 8% of TOTAL MEM
Thanks
Best Regards
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1 year
- 4
- 16
[PATCH] symbols: handle module symbols outside strbuf
by Stephen Brennan
Module symbol names can get overwritten by live patches or ksplice in
odd corner cases, so that the pointer no longer points within the string
buffer. Gracefully fallback to reading the string directly from the
kernel image in these cases, to avoid possible segmentation faults
reading outside the bounds of strbuf.
Signed-off-by: Stephen Brennan <stephen.s.brennan(a)oracle.com>
---
Hi folks - I encountered a segfault on a vmcore which had a module
symbol that had gotten its name overwritten by a ksplice (live patch).
It seems like there's not a guarantee that module symbol names _must_
live within the same symbol buffer, and there is even logic to prevent
reading too much data into strbuf in those cases.
This patch simply ensures that symbol names which start outside of the
strbuf which we copied, are read directly from the kernel image, rather
than indexing past the bounds of strbuf. I encountered this in
store_module_symbols_v2() and have tested it there, but I replicated the
code to the other versions. I will try to test it out on the other
variants as well, but I thought I'd share the patch now.
symbols.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/symbols.c b/symbols.c
index 176c950..e70dd69 100644
--- a/symbols.c
+++ b/symbols.c
@@ -1704,7 +1704,7 @@ store_module_symbols_v1(ulong total, int mods_installed)
BZERO(buf1, BUFSIZE);
- if (strbuf)
+ if (strbuf && (unsigned long)modsym->name - first < strbuflen)
strcpy(buf1,
&strbuf[(ulong)modsym->name - first]);
else
@@ -2080,7 +2080,7 @@ store_module_symbols_6_4(ulong total, int mods_installed)
BZERO(buf1, BUFSIZE);
- if (strbuf)
+ if (strbuf && modsym_name(syms, modsym, i) - first < strbuflen)
strcpy(buf1, &strbuf[modsym_name(syms, modsym, i) - first]);
else
read_string(modsym_name(syms, modsym, i), buf1, BUFSIZE-1);
@@ -2148,7 +2148,7 @@ store_module_symbols_6_4(ulong total, int mods_installed)
BZERO(buf1, BUFSIZE);
- if (strbuf)
+ if (strbuf && modsym_name(gpl_syms, modsym, i) - first < strbuflen)
strcpy(buf1, &strbuf[modsym_name(gpl_syms, modsym, i) - first]);
else
read_string(modsym_name(gpl_syms, modsym, i), buf1, BUFSIZE-1);
@@ -2456,7 +2456,7 @@ store_module_symbols_v2(ulong total, int mods_installed)
BZERO(buf1, BUFSIZE);
- if (strbuf)
+ if (strbuf && modsym_name(syms, modsym, i) - first < strbuflen)
strcpy(buf1,
&strbuf[modsym_name(syms, modsym, i) - first]);
else
@@ -2529,7 +2529,7 @@ store_module_symbols_v2(ulong total, int mods_installed)
BZERO(buf1, BUFSIZE);
- if (strbuf)
+ if (strbuf && modsym_name(gpl_syms, modsym, i) - first < strbuflen)
strcpy(buf1,
&strbuf[modsym_name(gpl_syms, modsym, i) - first]);
else
--
2.39.3
1 year
- 2
- 3
Re: [PATCH 0/3] s390x: uncouple physical and virtual memory spaces
by Lianbo Jiang
Hi, Alexander
Thank you for the patch set.
On 11/29/23 22:12, devel-request(a)lists.crash-utility.osci.io wrote:
> Date: Wed, 29 Nov 2023 13:47:33 +0100
> From: Alexander Gordeev <agordeev(a)linux.ibm.com>
> Subject: [Crash-utility] [PATCH 0/3] s390x: uncouple physical and
> virtual memory spaces
> To: devel(a)lists.crash-utility.osci.io
> Message-ID: <cover.1701256901.git.agordeev(a)linux.ibm.com>
>
> Hi all,
>
> Currently physical and virtual addresses are the same on S390X,
> but in the future it is going to be uncoupled just like on any
> other architecture. This series supports that feature, but it
> does not impact the current and older kernel versions.
I did the test, and the patches can work on old kernel versions.
However, since VA and PA are the same on S390x, it's hard to determine
if all changes have been made.
In addition, I can not test the patch 3, seems that the current kernel
does not support this feature(I tried it on the kernel 6.7, did not see
the different VA and PA).
Anyway, If you still want to have these patches in crash-utility for
now, I can help ack this one.
> Patch 2 is basically NOP and only fix semantics.
> Patch 3 uses the feature if it is available in kernel.
For patch 3, I saw a warning:
s390x.c: In function ‘is_read_proc_kcore’:
s390x.c:671:13: warning: unused variable ‘kcore_fd’ [-Wunused-variable]
671 | int kcore_fd, fd;
| ^~~~~~~~
The variable kcore_fd is not used in the patch 3, it would be good to
remove it.
Thanks
Lianbo
>
> Thanks!
>
> Alexander Gordeev (3):
> Fix identity_map_base value dump on S390
> s390x: fix virtual vs physical address confusion
> s390x: uncouple physical and virtual memory spaces
>
> defs.h | 20 ++++-
> s390.c | 2 +-
> s390x.c | 245 ++++++++++++++++++++++++++++++++++++++++++++++++++++++--
> 3 files changed, 255 insertions(+), 12 deletions(-)
>
1 year
- 2
- 2
[PATCH 1/2] Add a new helper function get_value_vmcore
by Huang Shijie
Add get_value_vmcore() to get the symbol value for @name.
Also add macro GET_SYM to simplify the code.
Signed-off-by: Huang Shijie <shijie(a)os.amperecomputing.com>
---
defs.h | 1 +
kernel.c | 85 +++++++++++++++++++-------------------------------------
2 files changed, 30 insertions(+), 56 deletions(-)
diff --git a/defs.h b/defs.h
index 1fe2d0b..eec7b3e 100644
--- a/defs.h
+++ b/defs.h
@@ -6055,6 +6055,7 @@ int hide_offline_cpu(int);
int get_highest_cpu_online(void);
int get_highest_cpu_present(void);
int get_cpus_to_display(void);
+bool get_value_vmcore(const char *name, ulong *v);
void get_log_from_vmcoreinfo(char *file);
int in_cpu_map(int, int);
void paravirt_init(void);
diff --git a/kernel.c b/kernel.c
index 6dcf414..caf6149 100644
--- a/kernel.c
+++ b/kernel.c
@@ -104,6 +104,20 @@ static void check_vmcoreinfo(void);
static int is_pvops_xen(void);
static int get_linux_banner_from_vmlinux(char *, size_t);
+/* Return TRUE if we succeed, return FALSE on failure. */
+bool
+get_value_vmcore(const char *name, ulong *v)
+{
+ char *string = pc->read_vmcoreinfo(name);
+
+ if (!string)
+ return FALSE;
+
+ *v = htol(string, RETURN_ON_ERROR, NULL);
+ free(string);
+ return TRUE;
+}
+
/*
* popuplate the global kernel table (kt) with kernel version
* information parsed from UTSNAME/OSRELEASE string
@@ -10984,6 +10998,12 @@ hypervisor_init(void)
fprintf(fp, "hypervisor: %s\n", kt->hypervisor);
}
+#define GET_SYM(s,v) \
+ if (get_value_vmcore((s), &(v))) { \
+ if (CRASHDEBUG(1)) \
+ fprintf(fp, s ": %lx\n", v); \
+ }
+
/*
* Get and display the kernel log buffer using the vmcoreinfo
* data alone without the vmlinux file.
@@ -11024,62 +11044,15 @@ get_log_from_vmcoreinfo(char *file)
} else
error(FATAL, "VMCOREINFO: cannot determine page size\n");
- if ((string = pc->read_vmcoreinfo("SYMBOL(log_buf)"))) {
- vmc->log_buf_SYMBOL = htol(string, RETURN_ON_ERROR, NULL);
- if (CRASHDEBUG(1))
- fprintf(fp, "SYMBOL(log_buf): %lx\n",
- vmc->log_buf_SYMBOL);
- free(string);
- }
- if ((string = pc->read_vmcoreinfo("SYMBOL(log_end)"))) {
- vmc->log_end_SYMBOL = htol(string, RETURN_ON_ERROR, NULL);
- if (CRASHDEBUG(1))
- fprintf(fp, "SYMBOL(log_end): %lx\n",
- vmc->log_end_SYMBOL);
- free(string);
- }
- if ((string = pc->read_vmcoreinfo("SYMBOL(log_buf_len)"))) {
- vmc->log_buf_len_SYMBOL = htol(string, RETURN_ON_ERROR, NULL);
- if (CRASHDEBUG(1))
- fprintf(fp, "SYMBOL(log_buf_len): %lx\n",
- vmc->log_buf_len_SYMBOL);
- free(string);
- }
- if ((string = pc->read_vmcoreinfo("SYMBOL(logged_chars)"))) {
- vmc->logged_chars_SYMBOL = htol(string, RETURN_ON_ERROR, NULL);
- if (CRASHDEBUG(1))
- fprintf(fp, "SYMBOL(logged_chars): %lx\n",
- vmc->logged_chars_SYMBOL);
- free(string);
- }
- if ((string = pc->read_vmcoreinfo("SYMBOL(log_first_idx)"))) {
- vmc->log_first_idx_SYMBOL = htol(string, RETURN_ON_ERROR, NULL);
- if (CRASHDEBUG(1))
- fprintf(fp, "SYMBOL(log_first_idx): %lx\n",
- vmc->log_first_idx_SYMBOL);
- free(string);
- }
- if ((string = pc->read_vmcoreinfo("SYMBOL(log_next_idx)"))) {
- vmc->log_next_idx_SYMBOL = htol(string, RETURN_ON_ERROR, NULL);
- if (CRASHDEBUG(1))
- fprintf(fp, "SYMBOL(log_next_idx): %lx\n",
- vmc->log_next_idx_SYMBOL);
- free(string);
- }
- if ((string = pc->read_vmcoreinfo("SYMBOL(phys_base)"))) {
- vmc->phys_base_SYMBOL = htol(string, RETURN_ON_ERROR, NULL);
- if (CRASHDEBUG(1))
- fprintf(fp, "SYMBOL(phys_base): %lx\n",
- vmc->phys_base_SYMBOL);
- free(string);
- }
- if ((string = pc->read_vmcoreinfo("SYMBOL(_stext)"))) {
- vmc->_stext_SYMBOL = htol(string, RETURN_ON_ERROR, NULL);
- if (CRASHDEBUG(1))
- fprintf(fp, "SYMBOL(_stext): %lx\n",
- vmc->_stext_SYMBOL);
- free(string);
- }
+ GET_SYM("SYMBOL(log_buf)", vmc->log_buf_SYMBOL);
+ GET_SYM("SYMBOL(log_end)", vmc->log_end_SYMBOL);
+ GET_SYM("SYMBOL(log_buf_len)", vmc->log_buf_len_SYMBOL);
+ GET_SYM("SYMBOL(logged_chars)", vmc->logged_chars_SYMBOL);
+ GET_SYM("SYMBOL(log_first_idx)", vmc->log_first_idx_SYMBOL);
+ GET_SYM("SYMBOL(log_next_idx)", vmc->log_next_idx_SYMBOL);
+ GET_SYM("SYMBOL(phys_base)", vmc->phys_base_SYMBOL);
+ GET_SYM("SYMBOL(_stext)", vmc->_stext_SYMBOL);
+
if ((string = pc->read_vmcoreinfo("OFFSET(log.ts_nsec)"))) {
vmc->log_ts_nsec_OFFSET = dtol(string, RETURN_ON_ERROR, NULL);
if (CRASHDEBUG(1))
--
2.40.1
1 year
- 4
- 14
[PATCH v2] symbols: expand all kernel module symtable if not all expanded previously
by Tao Liu
There is an issue that, for kernel modules, "dis -rl" fails to display
module's code line number data after execute "bt" cmd in crash.
Without the patch:
crsah> mod -S
crash> bt
PID: 1500 TASK: ff2bd8b093524000 CPU: 16 COMMAND: "lpfc_worker_0"
#0 [ff2c9f725c39f9e0] machine_kexec at ffffffff8e0686d3
...snip...
#7 [ff2c9f725c39fc00] page_fault at ffffffff8ea0114e
[exception RIP: lpfc_nlp_get+210]
RIP: ffffffffc0f60f82 RSP: ff2c9f725c39fcb0 RFLAGS: 00010046
RAX: 0000000000000046 RBX: ff2bd8d8ac056000 RCX: 0000000000fffffc
RDX: 0000000000000000 RSI: 0000000000000046 RDI: 0000000000000046
RBP: ff2bd8d8ac056090 R8: 0000000000000000 R9: 0000000000000000
R10: ff2bd90d1f8701c0 R11: 0000000000000001 R12: ff2bd93320482ae0
R13: ff2bd93051a80524 R14: ff2bd93051a80000 R15: ff2bd9332079fc00
ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
#8 [ff2c9f725c39fcc0] __lpfc_sli_release_iocbq_s4 at ffffffffc0f2f425 [lpfc]
...snip...
crash> dis -rl ffffffffc0f60f82
0xffffffffc0f60eb0 <lpfc_nlp_get>: nopl 0x0(%rax,%rax,1) [FTRACE NOP]
0xffffffffc0f60eb5 <lpfc_nlp_get+5>: push %rbp
0xffffffffc0f60eb6 <lpfc_nlp_get+6>: push %rbx
0xffffffffc0f60eb7 <lpfc_nlp_get+7>: test %rdi,%rdi
With the patch:
crash> mod -S
crash> bt
PID: 1500 TASK: ff2bd8b093524000 CPU: 16 COMMAND: "lpfc_worker_0"
#0 [ff2c9f725c39f9e0] machine_kexec at ffffffff8e0686d3
...snip...
#7 [ff2c9f725c39fc00] page_fault at ffffffff8ea0114e
[exception RIP: lpfc_nlp_get+210]
RIP: ffffffffc0f60f82 RSP: ff2c9f725c39fcb0 RFLAGS: 00010046
RAX: 0000000000000046 RBX: ff2bd8d8ac056000 RCX: 0000000000fffffc
RDX: 0000000000000000 RSI: 0000000000000046 RDI: 0000000000000046
RBP: ff2bd8d8ac056090 R8: 0000000000000000 R9: 0000000000000000
R10: ff2bd90d1f8701c0 R11: 0000000000000001 R12: ff2bd93320482ae0
R13: ff2bd93051a80524 R14: ff2bd93051a80000 R15: ff2bd9332079fc00
ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
#8 [ff2c9f725c39fcc0] __lpfc_sli_release_iocbq_s4 at ffffffffc0f2f425 [lpfc]
...snip...
crash> dis -rl ffffffffc0f60f82
/usr/src/debug/kernel-4.18.0-425.13.1.el8_7/linux-4.18.0-425.13.1.el8_7.x86_64/drivers/scsi/lpfc/lpfc_hbadisc.c: 6756
0xffffffffc0f60eb0 <lpfc_nlp_get>: nopl 0x0(%rax,%rax,1) [FTRACE NOP]
/usr/src/debug/kernel-4.18.0-425.13.1.el8_7/linux-4.18.0-425.13.1.el8_7.x86_64/drivers/scsi/lpfc/lpfc_hbadisc.c: 6759
0xffffffffc0f60eb5 <lpfc_nlp_get+5>: push %rbp
The root cause is, after kernel module been loaded by command mod, the symtable
is not expanded in gdb side. crash command bt or dis will trigger such an
expansion. However the symtable expansion is different for the 2 commands:
The stack trace of "dis -rl" for symtable expanding:
#0 0x00000000008d8d9f in add_compunit_symtab_to_objfile (cu=cu@entry=0xe6a77a0) at symfile.c:2914
#1 0x00000000006d3293 in buildsym_compunit::end_symtab_with_blockvector (this=<optimized out>, static_block=static_block@entry=0xfbe4b60, section=1, expandable=expandable@entry=0) at buildsym.c:1072
#2 0x00000000006d336a in buildsym_compunit::end_symtab_from_static_block (this=<optimized out>, static_block=static_block@entry=0xfbe4b60, section=<optimized out>, expandable=expandable@entry=0) at buildsym.c:1106
#3 0x000000000077e8e9 in process_full_comp_unit (pretend_language=<optimized out>, cu=0x8ee4c60) at /usr/include/c++/8/bits/unique_ptr.h:716
#4 process_queue (per_objfile=0xc54c870) at dwarf2/read.c:9220
#5 dw2_do_instantiate_symtab (per_cu=<optimized out>, per_objfile=0xc54c870, skip_partial=<optimized out>) at dwarf2/read.c:2448
#6 0x000000000077ed67 in dw2_instantiate_symtab (per_cu=0xdd0a320, per_objfile=0xc54c870, skip_partial=<optimized out>) at dwarf2/read.c:2472
#7 0x000000000077f75e in dw2_expand_all_symtabs (objfile=<optimized out>) at dwarf2/read.c:3768
#8 0x00000000008f254d in gdb_get_line_number (req=0x7fffffffb1f0) at symtab.c:7112
#9 0x00000000008f22af in gdb_command_funnel_1 (req=0x7fffffffb1f0) at symtab.c:7023
#10 0x00000000008f2003 in gdb_command_funnel (req=0x7fffffffb1f0) at symtab.c:6965
#11 0x00000000005b7f02 in gdb_interface (req=req@entry=0x7fffffffb1f0) at gdb_interface.c:409
#12 0x00000000005f5bd8 in get_line_number (addr=18446744072651935408, buf=buf@entry=0x7fffffffd460 "", reserved=reserved@entry=0) at symbols.c:4440
#13 0x000000000059e574 in cmd_dis () at kernel.c:2143
The stack trace of "bt" for symtable expanding:
#0 0x00000000008d8d9f in add_compunit_symtab_to_objfile (cu=cu@entry=0x1ad15630) at symfile.c:2914
#1 0x00000000006d3293 in buildsym_compunit::end_symtab_with_blockvector (this=<optimized out>, static_block=static_block@entry=0x1db0be30, section=1, expandable=expandable@entry=0) at buildsym.c:1072
#2 0x00000000006d336a in buildsym_compunit::end_symtab_from_static_block (this=<optimized out>, static_block=static_block@entry=0x1db0be30, section=<optimized out>, expandable=expandable@entry=0) at buildsym.c:1106
#3 0x000000000077e8e9 in process_full_comp_unit (pretend_language=<optimized out>, cu=0x7465240) at /usr/include/c++/8/bits/unique_ptr.h:716
#4 process_queue (per_objfile=0xc113810) at dwarf2/read.c:9220
#5 dw2_do_instantiate_symtab (per_cu=<optimized out>, per_objfile=0xc113810, skip_partial=<optimized out>) at dwarf2/read.c:2448
#6 0x000000000077ed67 in dw2_instantiate_symtab (per_cu=0xdd069d0, per_objfile=0xc113810, skip_partial=<optimized out>) at dwarf2/read.c:2472
#7 0x000000000077f8ed in dw2_lookup_symbol (objfile=<optimized out>, block_index=STATIC_BLOCK, name=0x7fffffffc890 "cpumask_t", domain=STRUCT_DOMAIN) at dwarf2/read.c:3669
#8 0x00000000008e6d03 in lookup_symbol_via_quick_fns (objfile=0xdd277a0, block_index=STATIC_BLOCK, name=0x7fffffffc890 "cpumask_t", domain=STRUCT_DOMAIN) at symtab.c:2392
#9 0x00000000008e7153 in lookup_symbol_in_objfile (objfile=0xdd277a0, block_index=STATIC_BLOCK, name=0x7fffffffc890 "cpumask_t", domain=STRUCT_DOMAIN) at symtab.c:2541
#10 0x00000000008e73c6 in lookup_symbol_global_or_static_iterator_cb (objfile=0xdd277a0, cb_data=0x7fffffffc470) at symtab.c:2615
#11 0x00000000008b99c4 in svr4_iterate_over_objfiles_in_search_order (gdbarch=<optimized out>, cb=0x8e7342 <lookup_symbol_global_or_static_iterator_cb(objfile*, void*)>, cb_data=0x7fffffffc470, current_objfile=0x0) at solib-svr4.c:3248
#12 0x00000000008e754e in lookup_global_or_static_symbol (name=0x7fffffffc890 "cpumask_t", block_index=STATIC_BLOCK, objfile=0x0, domain=STRUCT_DOMAIN) at symtab.c:2660
#13 0x00000000008e75da in lookup_static_symbol (name=0x7fffffffc890 "cpumask_t", domain=STRUCT_DOMAIN) at symtab.c:2678
#14 0x00000000008e632c in lookup_symbol_aux (name=0x7fffffffc890 "cpumask_t", match_type=symbol_name_match_type::FULL, block=0x0, domain=STRUCT_DOMAIN, language=language_c, is_a_field_of_this=0x0) at symtab.c:2122
#15 0x00000000008e5a7a in lookup_symbol_in_language (name=0x7fffffffc890 "cpumask_t", block=0x0, domain=STRUCT_DOMAIN, lang=language_c, is_a_field_of_this=0x0) at symtab.c:1889
#16 0x00000000008e5b30 in lookup_symbol (name=0x7fffffffc890 "cpumask_t", block=0x0, domain=STRUCT_DOMAIN, is_a_field_of_this=0x0) at symtab.c:1915
#17 0x00000000008f2a4a in gdb_get_datatype (req=0x7fffffffc730) at symtab.c:7229
#18 0x00000000008f22c0 in gdb_command_funnel_1 (req=0x7fffffffc730) at symtab.c:7027
#19 0x00000000008f2003 in gdb_command_funnel (req=0x7fffffffc730) at symtab.c:6965
#20 0x00000000005b7f02 in gdb_interface (req=req@entry=0x7fffffffc730) at gdb_interface.c:409
#21 0x00000000005f8a9f in datatype_info (name=name@entry=0xa8454d "cpumask_t", member=member@entry=0x0, dm=dm@entry=0xfffffffffffffffc) at symbols.c:5715
#22 0x0000000000599947 in cpu_map_size (type=<optimized out>) at kernel.c:913
#23 0x00000000005a975d in get_cpus_online () at kernel.c:9556
#24 0x0000000000637a8b in diskdump_get_prstatus_percpu (cpu=16) at diskdump.c:2277
#25 0x000000000062f0e4 in get_netdump_regs_x86_64 (bt=0x7fffffffd950, ripp=0x7fffffffd130, rspp=0x7fffffffd138) at netdump.c:3471
#26 0x000000000059fe68 in back_trace (bt=bt@entry=0x7fffffffd950) at kernel.c:3092
#27 0x00000000005ab1cb in cmd_bt () at kernel.c:2859
For the stacktrace of "dis -rl", it calls dw2_expand_all_symtabs() to expand
all symtable of the objfile, or "*.ko.debug" in our case. However for
the stacktrace of "bt", it doesn't expand all, but only a subset of symtable
which is enough to find a symbol by dw2_lookup_symbol(). As a result, the
objfile->compunit_symtabs, which is the head of a single linked list of
struct compunit_symtab, is not NULL but didn't contain all symtables. It
will not be reinitialized in gdb_get_line_number() by "dis -rl" because
!objfile_has_full_symbols(objfile) check will fail, so it cannot display
the proper code line number data.
Since objfile_has_full_symbols(objfile) check cannot ensure all symbols
been expanded, this patch add a new member as a flag for struct objfile
to record if all symbols have been expanded. The flag will be set only ofter
expand_all_symtabs been called.
Signed-off-by: Tao Liu <ltao(a)redhat.com>
---
v1 -> v2: new method for kernel module symtabs expansion.
v1: expand all kernel modules symtabs when loading by mod -s/-S
v2: record if a specific kernel module's symtab been all expanded,
and skip re-expansion if true.
---
gdb-10.2.patch | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 50 insertions(+)
diff --git a/gdb-10.2.patch b/gdb-10.2.patch
index d81030d..2f7d585 100644
--- a/gdb-10.2.patch
+++ b/gdb-10.2.patch
@@ -3187,3 +3187,53 @@ exit 0
result = stringtab + symbol_entry->_n._n_n._n_offset;
}
else
+--- gdb-10.2/gdb/objfiles.h.orig
++++ gdb-10.2/gdb/objfiles.h
+@@ -712,6 +712,8 @@ struct objfile
+ next time. If an objfile does not have the symbols, it will
+ never have them. */
+ bool skip_jit_symbol_lookup = false;
++
++ bool all_symtabs_expanded = false;
+ };
+
+ /* A deleter for objfile. */
+--- gdb-10.2/gdb/symfile.c.orig
++++ gdb-10.2/gdb/symfile.c
+@@ -1133,8 +1133,10 @@ symbol_file_add_with_addrs (bfd *abfd, const char *name,
+ printf_filtered (_("Expanding full symbols from %ps...\n"),
+ styled_string (file_name_style.style (), name));
+
+- if (objfile->sf)
++ if (objfile->sf) {
+ objfile->sf->qf->expand_all_symtabs (objfile);
++ objfile->all_symtabs_expanded = true;
++ }
+ }
+
+ /* Note that we only print a message if we have no symbols and have
+--- gdb-10.2/gdb/symtab.c.orig
++++ gdb-10.2/gdb/symtab.c
+@@ -7097,8 +7097,9 @@ gdb_get_line_number(struct gnu_request *req)
+ */
+ if (req->lm) {
+ objfile = req->lm->loaded_objfile;
+- if (!objfile_has_full_symbols(objfile) && objfile->sf) {
++ if (!objfile->all_symtabs_expanded && objfile->sf) {
+ objfile->sf->qf->expand_all_symtabs(objfile);
++ objfile->all_symtabs_expanded = true;
+ sal = find_pc_line(pc, 0);
+ }
+ }
+@@ -7761,8 +7765,10 @@ iterate_datatypes (struct gnu_request *req)
+ {
+ for (objfile *objfile : current_program_space->objfiles ())
+ {
+- if (objfile->sf)
++ if (objfile->sf) {
+ objfile->sf->qf->expand_all_symtabs(objfile);
++ objfile->all_symtabs_expanded = true;
++ }
+
+ for (compunit_symtab *cust : objfile->compunits ())
+ {
--
2.40.1
1 year
- 3
- 10