Re: [Crash-utility] [Crash Utility] Improvement for getting offline CPU register without symbol "crash_notes"

Dear Maintaniners, Sorry for attaching a not readable patch file at previous mail. I add the diff of the patch inline for your review.

And provide the reason of improvement again and look forward for your feedback. We want to improve the crash_tool for the case that need offline cpu register info even Kdump without crash_notes. For one thing, we will prepare a Kdump with all CPU register info in ELF note.

For another thing, we need to modify crash_tool and make it support adding offline cpu register info even Kdump without crash_notes. Signed-off-by: Nicholas Tang <Nicholas.tang(a)mediatek.com&gt; --- crash-7.3.0/arm64.c 2021-04-27 16:01:07.000000000 +0800 +++ crash-7.3.0.mod/arm64.c 2021-06-15 17:13:54.037273227 +0800 @@ -3667,8 +3667,41 @@ arm64_get_crash_notes(void) ulong *notes_ptrs; ulong i, found; - if (!symbol_exists("crash_notes")) + if (!symbol_exists("crash_notes")) { + if (DISKDUMP_DUMPFILE() || KDUMP_DUMPFILE()) { + if (!(ms->panic_task_regs = calloc((size_t)kt->cpus, sizeof(struct arm64_pt_regs)))) + error(FATAL, "cannot calloc panic_task_regs space\n"); + + for (i = found = 0; i < kt->cpus; i++) { + if (DISKDUMP_DUMPFILE()) + note = diskdump_get_prstatus_percpu(i); + else if (KDUMP_DUMPFILE()) + note = netdump_get_prstatus_percpu(i); + else { + error(WARNING, "cpu %d: cannot find NT_PRSTATUS note\n", i); + continue; + } + + /* + * Find correct location of note data. This contains elf_prstatus + * structure which has registers etc. for the crashed task. + */ + offset = sizeof(Elf64_Nhdr); + offset = roundup(offset + note->n_namesz, 4); + p = (char *)note + offset; /* start of elf_prstatus */ + + BCOPY(p + OFFSET(elf_prstatus_pr_reg), &ms->panic_task_regs[i], + sizeof(struct arm64_pt_regs)); + + found++; + } + } + if (!found) { + free(ms->panic_task_regs); + ms->panic_task_regs = NULL; + } return; + } crash_notes = symbol_value("crash_notes"); BR James Hsu From: James Hsu (徐慶�) Sent: Wednesday, July 7, 2021 3:11 PM To: crash-utility(a)redhat.com Cc: Nicholas Tang (鄭秦輝); James Hsu (徐慶�) Subject: [Crash Utility] Improvement for getting offline CPU register without symbol "crash_notes" Dear crash_tool maintainers, We want to improve the crash_tool for the case that need offline cpu register info even Kdump without crash_notes. For one thing, we will prepare a Kdump with all CPU register info in ELF note. For another thing, we need to modify crash_tool and make it support adding offline cpu register info even Kdump without crash_notes. We prepare a patch for the case with ARCH=arm64. Please take your time to review our patch and look forward to receving your comments. BR James Hsu *********************MEDIATEK Confidential/Internal Use********************* ************* MEDIATEK Confidentiality Notice ******************** The information contained in this e-mail message (including any attachments) may be confidential, proprietary, privileged, or otherwise exempt from disclosure under applicable laws. It is intended to be conveyed only to the designated recipient(s). Any use, dissemination, distribution, printing, retaining or copying of this e-mail (including its attachments) by unintended recipient(s) is strictly prohibited and may be unlawful. If you are not an intended recipient of this e-mail, or believe that you have received this e-mail in error, please notify the sender immediately (by replying to this e-mail), delete any and all copies of this e-mail (including any attachments) from your system, and do not disclose the content of this e-mail to any other person. Thank you!