[Crash-utility] Re: [PATCH RESEND] Add a command line option to retrieve build-id

Hi, Munehisa Thank you for the patch. On Tue, Dec 9, 2025 at 2:18 AM <devel-request(a)lists.crash-utility.osci.io&gt; wrote: > > Date: Mon, 8 Dec 2025 10:16:17 -0800 > From: Munehisa Kamata <kamatam(a)amazon.com&gt; > Subject: [Crash-utility] [PATCH RESEND] Add a command line option to > retrieve build-id > To: <devel(a)lists.crash-utility.osci.io&gt; > Cc: Munehisa Kamata <kamatam(a)amazon.com&gt; > Message-ID: <20251208181617.420350-1-kamatam(a)amazon.com&gt; > Content-Type: text/plain > > Resending because my previous post is held for presumably being sent > without a list subscription. > > Since Linux kernel commit 0935288c6e00 ("kdump: append kernel build-id > string to VMCOREINFO") merged in v5.9, VMCOREINFO data contains a kernel > build-id. Add a simple --build-id command line option that retrieves the > build-id from a kernel dump file, which works just like the existing > --osrelease option (and the implementation mimics it). > > Example: > # crash --build-id /var/crash/127.0.0.1-2025-11-28-00\:33\:07/vmcore > 03cc3b4eb67df4e66a6a794a39521bafabef0886 > This looks good to me. So for the patch: Ack Lianbo > While we may also want to implement the strict build-id based > verification between namelist and dump file, this would be still handy > for some scripting or automation tasks without namelist. > > Signed-off-by: Munehisa Kamata <kamatam(a)amazon.com&gt; > --- > crash.8 | 7 +++++++ > defs.h | 1 + > diskdump.c | 17 +++++++++++++++++ > help.c | 6 ++++++ > main.c | 30 ++++++++++++++++++++++++++++++ > makedumpfile.c | 40 ++++++++++++++++++++++++++++++++++------ > netdump.c | 17 +++++++++++++++++ > 7 files changed, 112 insertions(+), 6 deletions(-) > > diff --git a/crash.8 b/crash.8 > index c7dc27d..4c06cb7 100644 > --- a/crash.8 > +++ b/crash.8 > @@ -398,6 +398,13 @@ Display the OSRELEASE vmcoreinfo string from a kdump > .I dumpfile > header. > .TP > +.BI --build-id \ dumpfile > +Display the BUILD-ID vmcoreinfo string from a kdump > +.I dumpfile > +header. > +Note: this option only works for kernel (>=v5.9); otherwise it > +prints "unknown" and exits with non-zero status. > +.TP > .BI --hyper > Force the session to be that of a Xen hypervisor. > .TP > diff --git a/defs.h b/defs.h > index 24dad93..ff8041c 100644 > --- a/defs.h > +++ b/defs.h > @@ -570,6 +570,7 @@ struct program_context { > #define MEMSRC_LOCAL (0x80000ULL) > #define REDZONE (0x100000ULL) > #define VMWARE_VMSS_GUESTDUMP (0x200000ULL) > +#define GET_BUILD_ID (0x400000ULL) > char *cleanup; > char *namelist_orig; > char *namelist_debug_orig; > diff --git a/diskdump.c b/diskdump.c > index b1ca0a7..0ff8782 100644 > --- a/diskdump.c > +++ b/diskdump.c > @@ -91,6 +91,7 @@ static void dump_vmcoreinfo(FILE *); > static void dump_note_offsets(FILE *); > static char *vmcoreinfo_read_string(const char *); > static void diskdump_get_osrelease(void); > +static void diskdump_get_build_id(void); > static int valid_note_address(unsigned char *); > > /* For split dumpfile */ > @@ -1074,6 +1075,9 @@ is_diskdump(char *file) > if (pc->flags2 & GET_OSRELEASE) > diskdump_get_osrelease(); > > + if (pc->flags2 & GET_BUILD_ID) > + diskdump_get_build_id(); > + > #ifdef LZO > if (lzo_init() == LZO_E_OK) > dd->flags |= LZO_SUPPORTED; > @@ -2446,6 +2450,19 @@ diskdump_get_osrelease(void) > pc->flags2 &= ~GET_OSRELEASE; > } > > +static void > +diskdump_get_build_id(void) > +{ > + char *string; > + > + if ((string = vmcoreinfo_read_string("BUILD-ID"))) { > + fprintf(fp, "%s\n", string); > + free(string); > + } > + else > + pc->flags2 &= ~GET_BUILD_ID; > +} > + > static int > valid_note_address(unsigned char *offset) > { > diff --git a/help.c b/help.c > index 78d7a5c..1a21062 100644 > --- a/help.c > +++ b/help.c > @@ -266,6 +266,12 @@ char *program_usage_info[] = { > " Display the OSRELEASE vmcoreinfo string from a kdump dumpfile", > " header.", > "", > + " --build-id dumpfile", > + " Display the BUILD-ID vmcoreinfo string from a kdump dumpfile", > + " header.", > + " Note: this option only works for kernel(>=v5.9); otherwise it", > + " prints \"unknown\" and exits with non-zero status", > + "", > " --hyper", > " Force the session to be that of a Xen hypervisor.", > "", > diff --git a/main.c b/main.c > index 71bcc15..d4c335b 100644 > --- a/main.c > +++ b/main.c > @@ -29,6 +29,7 @@ static void check_xen_hyper(void); > static void show_untrusted_files(void); > static void get_osrelease(char *); > static void get_log(char *); > +static void get_build_id(char *); > > static struct option long_options[] = { > {"memory_module", required_argument, 0, 0}, > @@ -66,6 +67,7 @@ static struct option long_options[] = { > {"no_elf_notes", 0, 0, 0}, > {"osrelease", required_argument, 0, 0}, > {"log", required_argument, 0, 0}, > + {"build-id", required_argument, 0, 0}, > {"hex", 0, 0, 0}, > {"dec", 0, 0, 0}, > {"no_strip", 0, 0, 0}, > @@ -276,6 +278,11 @@ main(int argc, char **argv) > get_log(optarg); > } > > + else if (STREQ(long_options[option_index].name, "build-id")) { > + pc->flags2 |= GET_BUILD_ID; > + get_build_id(optarg); > + } > + > else if (STREQ(long_options[option_index].name, "hex")) { > pc->flags2 |= RADIX_OVERRIDE; > pc->output_radix = 16; > @@ -1502,6 +1509,8 @@ dump_program_context(void) > fprintf(fp, "%sREDZONE", others++ ? "|" : ""); > if (pc->flags2 & VMWARE_VMSS_GUESTDUMP) > fprintf(fp, "%sVMWARE_VMSS_GUESTDUMP", others++ ? "|" : ""); > + if (pc->flags2 & GET_BUILD_ID) > + fprintf(fp, "%sGET_BUILD_ID", others++ ? "|" : ""); > fprintf(fp, ")\n"); > > fprintf(fp, " namelist: %s\n", pc->namelist); > @@ -1972,6 +1981,27 @@ get_log(char *dumpfile) > clean_exit(retval); > } > > +static void > +get_build_id(char *dumpfile) > +{ > + int retval = 1; > + > + if (is_flattened_format(dumpfile)) { > + if (pc->flags2 & GET_BUILD_ID) > + retval = 0; > + } else if (is_diskdump(dumpfile)) { > + if (pc->flags2 & GET_BUILD_ID) > + retval = 0; > + } else if (is_kdump(dumpfile, KDUMP_LOCAL)) { > + if (pc->flags2 & GET_BUILD_ID) > + retval = 0; > + } > + > + if (retval) > + fprintf(fp, "unknown\n"); > + > + clean_exit(retval); > +} > > char * > no_vmcoreinfo(const char *unused) > diff --git a/makedumpfile.c b/makedumpfile.c > index 26d12b6..ee03199 100644 > --- a/makedumpfile.c > +++ b/makedumpfile.c > @@ -24,6 +24,7 @@ > #include <byteswap.h> > > static void flattened_format_get_osrelease(char *); > +static void flattened_format_get_build_id(char *); > > int flattened_format = 0; > > @@ -196,7 +197,7 @@ read_all_makedumpfile_data_header(char *file) > void > check_flattened_format(char *file) > { > - int fd, get_osrelease; > + int fd, get_osrelease, get_build_id; > struct stat stat; > struct makedumpfile_header fh; > > @@ -206,6 +207,12 @@ check_flattened_format(char *file) > } else > get_osrelease = FALSE; > > + if (pc->flags2 & GET_BUILD_ID) { > + get_build_id = TRUE; > + pc->flags2 &= ~GET_BUILD_ID; > + } else > + get_build_id = FALSE; > + > if (flattened_format) > goto out; > > @@ -237,6 +244,11 @@ check_flattened_format(char *file) > return; > } > > + if (get_build_id) { > + flattened_format_get_build_id(file); > + return; > + } > + > if (!read_all_makedumpfile_data_header(file)) > return; > > @@ -251,6 +263,9 @@ check_flattened_format(char *file) > out: > if (get_osrelease) > pc->flags2 |= GET_OSRELEASE; > + > + if (get_build_id) > + pc->flags2 |= GET_BUILD_ID; > } > > static int > @@ -368,26 +383,39 @@ dump_flat_header(FILE *ofp) > } > > static void > -flattened_format_get_osrelease(char *file) > +flattened_format_get_common(char *file, char *key, ulonglong flag) > { > int c; > FILE *pipe; > - char buf[BUFSIZE], *p1, *p2; > + char keybuf[BUFSIZE], buf[BUFSIZE], *p1, *p2; > > - c = strlen("OSRELEASE="); > + sprintf(keybuf, "%s=", key); > + c = strlen(keybuf); > sprintf(buf, "/usr/bin/strings -n %d %s", c, file); > > if ((pipe = popen(buf, "r")) == NULL) > return; > > for (c = 0; (c < 100) && fgets(buf, BUFSIZE-1, pipe); c++) { > - if ((p1 = strstr(buf, "OSRELEASE="))) { > + if ((p1 = strstr(buf, keybuf))) { > p2 = strstr(p1, "="); > fprintf(fp, "%s", p2+1); > flattened_format = TRUE; > - pc->flags2 |= GET_OSRELEASE; > + pc->flags2 |= flag; > } > } > > pclose(pipe); > } > + > +static void > +flattened_format_get_osrelease(char *file) > +{ > + flattened_format_get_common(file, "OSRELEASE", GET_OSRELEASE); > +} > + > +static void > +flattened_format_get_build_id(char *file) > +{ > + flattened_format_get_common(file, "BUILD-ID", GET_BUILD_ID); > +} > diff --git a/netdump.c b/netdump.c > index c7ff009..ba1c6c4 100644 > --- a/netdump.c > +++ b/netdump.c > @@ -50,6 +50,7 @@ static int proc_kcore_init_64(FILE *, int); > static char *get_regs_from_note(char *, ulong *, ulong *); > static void kdump_get_osrelease(void); > static char *vmcoreinfo_read_string(const char *); > +static void kdump_get_build_id(void); > > > #define ELFSTORE 1 > @@ -477,6 +478,10 @@ is_netdump(char *file, ulong source_query) > get_log_from_vmcoreinfo(file); > } > > + if ((source_query == KDUMP_LOCAL) && > + (pc->flags2 & GET_BUILD_ID)) > + kdump_get_build_id(); > + > return nd->header_size; > > bailout: > @@ -4996,6 +5001,18 @@ kdump_get_osrelease(void) > pc->flags2 &= ~GET_OSRELEASE; > } > > +static void > +kdump_get_build_id(void) > +{ > + char *string; > + > + if ((string = vmcoreinfo_read_string("BUILD-ID"))) { > + fprintf(fp, "%s\n", string); > + free(string); > + } else > + pc->flags2 &= ~GET_BUILD_ID; > +} > + > void > dump_registers_for_qemu_mem_dump(void) > { > -- > 2.47.3 -- 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