Re: [Crash-utility] ppc64 specific changes to support kdump vmcore

Haren Myneni wrote: >Reposting this patch as it did not made to crash mailing list. Dave, >Thanks for adding my different e-mail address to subscriber list. > > > No problem -- I prefer to keep this list subscriber-only to avoid the spam you see on other lists... >Dave, > >Attaching a patch which contains ppc64 specific changes to read kdump >vmcore. As we are saving pt_regs for all cpus, it reads them from vmcore >instead of looking for specific symbols, used for PPC64 netdump/diskdump >vmcore. Also, prints regs before any active backtrace. Whereas for >netdump vmcore, regs will be displayed anyway as part of exception frame >since the 'bt' command displays from the top frame. >Verified with "Make Warn" > >Please let me know if you have any comments. > > > This patch looks good. No comment... ;-) >As Badari mentioned, when the sparsemem is enabled, pg_dat->node_mem_map >member does not exists. mem_map for each node is scattered across >multiple sections and is not contiguous. Therefore, some detailed >changes are needed. Until we fix this issue, can we include some hack >so that users can use other commands for vmcore analysis. >The fix will be: > if (MEMBER_EXISTS("pglist_data", "node_mem_map")) > readmem(pgdat+OFFSET(pglist_data_node_mem_map), KVADDR, > &node_mem_map, sizeof(ulong), > "node_mem_map", FAULT_ON_ERROR); > >[I noticed your response to Badari's posting. Since the sparsemem is >effected only for powerpc at this point, we thought, user can use the >limited functionality with the above change. (Ex: bt) until we have the >complete fix. At least we will be having crash tool available for kdump >vmore on ppc64. The sparsemem issue will be fixed soon. Ok, please >ignore this if you prefer to wait for the complete fix] > > > I was tinkering around with this by simulating the bogus setting of "node_mem_map" above, and I'm surprised that you can get as much functionality as crash does give you. Most people probably wouldn't even notice. Anyway, I was about to change my mind, and put the EXISTS check in for now -- but along with a non-fatal error message that would be annoying enough for you guys to whip up a real fix. I'll still do that, unless by "fixed soon", you mean in a day or two? Dave

>Thanks >Haren > > ------------------------------------------------------------------------------------------------------------------------ >diff -Naurp crash-4.0-2.20.orig/netdump.c crash-4.0-2.20/netdump.c >--- crash-4.0-2.20.orig/netdump.c 2006-02-11 16:50:28.000000000 -0800 >+++ crash-4.0-2.20/netdump.c 2006-02-11 16:50:58.000000000 -0800 >@@ -1680,7 +1680,13 @@ get_netdump_regs_ppc64(struct bt_info *b > Elf64_Nhdr *note; > size_t len; > >- if (bt->task == tt->panic_task) { >+ if ((bt->task == tt->panic_task) || >+ (is_task_active(bt->task) && nd->num_prstatus_notes > 1)) { >+ /* >+ * Registers are saved during the dump process for the >+ * panic task. Whereas in kdump, regs are captured for all >+ * CPUs if they responded to an IPI. >+ */ > if (nd->num_prstatus_notes > 1) > note = (Elf64_Nhdr *) > nd->nt_prstatus_percpu[bt->tc->processor]; >diff -Naurp crash-4.0-2.20.orig/ppc64.c crash-4.0-2.20/ppc64.c >--- crash-4.0-2.20.orig/ppc64.c 2006-02-11 16:50:32.000000000 -0800 >+++ crash-4.0-2.20/ppc64.c 2006-02-13 16:10:56.000000000 -0800 >@@ -1420,20 +1420,11 @@ ppc64_check_eframe(struct ppc64_pt_regs > return NULL; > } > >-/* >- * Print exception frame information for ppc64 >- */ > static void >-ppc64_print_eframe(char *efrm_str, struct ppc64_pt_regs *regs, >- struct bt_info *bt) >+ppc64_print_regs(struct ppc64_pt_regs *regs) > { > int i; > >- if (BT_REFERENCE_CHECK(bt)) >- return; >- >- fprintf(fp, " %s [%lx] exception frame:", efrm_str, regs->trap); >- > /* print out the gprs... */ > for(i=0; i<32; i++) { > if(!(i % 3)) >@@ -1465,9 +1456,66 @@ ppc64_print_eframe(char *efrm_str, struc > fprintf(fp, "DAR: %016lx\n", regs->dar); > fprintf(fp, " DSISR: %016lx ", regs->dsisr); > fprintf(fp, " Syscall Result: %016lx\n", regs->result); >+} >+ >+/* >+ * Print the exception frame information >+ */ >+static void >+ppc64_print_eframe(char *efrm_str, struct ppc64_pt_regs *regs, >+ struct bt_info *bt) >+{ >+ if (BT_REFERENCE_CHECK(bt)) >+ return; >+ >+ fprintf(fp, " %s [%lx] exception frame:", efrm_str, regs->trap); >+ ppc64_print_regs(regs); > fprintf(fp, "\n"); > } > >+/* >+ * get SP and IP from the saved ptregs. >+ */ >+static int >+ppc64_kdump_stack_frame(struct bt_info *bt_in, ulong *nip, ulong *ksp) >+{ >+ struct ppc64_pt_regs *pt_regs; >+ unsigned long unip; >+ >+ pt_regs = (struct ppc64_pt_regs *)bt_in->machdep; >+ if (!pt_regs->gpr[1]) { >+ /* >+ * Not collected regs. May be the corresponding CPU not >+ * responded to an IPI. >+ */ >+ fprintf(fp, "%0lx: GPR1 register value (SP) was not saved\n", >+ bt_in->task); >+ return FALSE; >+ } >+ *ksp = pt_regs->gpr[1]; >+ readmem(*ksp+16, KVADDR, &unip, sizeof(ulong), "Regs NIP value", >+ FAULT_ON_ERROR); >+ *nip = unip; >+ >+ if (bt_in->flags && >+ ((BT_TEXT_SYMBOLS|BT_TEXT_SYMBOLS_PRINT|BT_TEXT_SYMBOLS_NOPRINT))) >+ return TRUE; >+ >+ /* >+ * Print the collected regs for the active task >+ */ >+ ppc64_print_regs(pt_regs); >+ >+ fprintf(fp, " NIP [%016lx] %s\n", pt_regs->nip, >+ closest_symbol(pt_regs->nip)); >+ if (unip != pt_regs->link) >+ fprintf(fp, " LR [%016lx] %s\n", pt_regs->link, >+ closest_symbol(pt_regs->link)); >+ >+ fprintf(fp, "\n"); >+ >+ return TRUE; >+} > > /* > * Get the starting point for the active cpus in a diskdump/netdump. >@@ -1485,12 +1533,18 @@ ppc64_get_dumpfile_stack_frame(struct bt > ulong ur_ksp = 0; > int check_hardirq, check_softirq; > int check_intrstack = TRUE; >+ struct ppc64_pt_regs *pt_regs; >+ >+ /* >+ * For the kdump vmcore, Use SP and IP values that are saved in ptregs. >+ */ >+ if (pc->flags && KDUMP) >+ return ppc64_kdump_stack_frame(bt_in, nip, ksp); > > bt = &bt_local; > BCOPY(bt_in, bt, sizeof(struct bt_info)); > ms = machdep->machspec; > ur_nip = ur_ksp = 0; >- struct ppc64_pt_regs *pt_regs; > > panic_task = tt->panic_task == bt->task ? TRUE : FALSE; > > > ------------------------------------------------------------------------------------------------------------------------ >-- >Crash-utility mailing list &gt;Crash-utility(a)redhat.com >https://www.redhat.com/mailman/listinfo/crash-utility > > -- Crash-utility mailing list Crash-utility(a)redhat.com https://www.redhat.com/mailman/listinfo/crash-utility