Re: [Crash-utility] arm64: Get CPU registers without crash_notes symbol

Dear Kazu, Sorry for late reply Thanks for your suggestion and I have prepared a V2 patch, please help to review.

BTW, I have switched to evolution mail system, if still look like html format, please let me know, thanks. Signed-off-by: James Hsu <james.hsu(a)mediatek.com&gt; diff --git a/arm64.c b/arm64.c index 8934961..03c8167 100644 --- a/arm64.c +++ b/arm64.c @@ -3667,8 +3667,42 @@ 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); + + if(!note) { + 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"); Thanks James Hsu On Wed, 2021-08-11 at 02:52 +0000, HAGIO KAZUHITO(萩尾　一仁) wrote: > -----Original Message----- > > > > Dear Crash 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. > > It is verified with our kdump without crash_note and can get all > > cpu register. > > Please take your time to review our patch and look forward to > > receiving your comments. > > > > Patch detail as below > > I've rewritten the commit log, is this ok? > -- > arm64: Get CPU registers from ELF notes even without crash_notes > symbol > > Currently arm64 crash retrieves the CPU registers from crash_notes > symbol > or ELF notes only when the symbol exists, but there are dumpfiles > which > have the registers in ELF notes without the symbol. > > With the patch, crash can retrieve the registers from ELF notes > without > the crash_notes symbol. > -- > > And please add Signed-off-by tag. > > > --- 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; > > + } > > This else block should be separated from the if block like this? > > if (!note) { > 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; > > + } > > This if block should be within the if (DISKDUMP_DUMPFILE()... block. > > > return; > > + } > > > > crash_notes = symbol_value("crash_notes"); > > > > (and this email still looks HTML one to me :-) > > Thanks, > Kazu >