Re: [Crash-utility] [PATCH] GDB: fix the failure of 'set scope' command

Currently, some command such as 'sys' may cause subsequent 'set scope' commands to fail because it may not find the correct symtab associated with PC and SECTION in the find_pc_sect_symtab(), eventually, this will cause the following failure: crash> mod -S 3.10.0-957.el7.x86_64 crash> mod -s dm_service_time crash> set scope st_create set: gdb cannot find text block for address: st_create crash> mod -d dm_service_time crash> mod -sr dm_service_time crash> set scope st_create scope: ffffffffc044d270 (st_create) crash> sys KERNEL: 3.10.0-957.el7.x86_64/vmlinux DUMPFILE: crash/vmcore [PARTIAL DUMP] CPUS: 48 DATE: Sat Aug 3 11:41:00 EDT 2019 UPTIME: 1 days, 10:28:48 LOAD AVERAGE: 2.95, 1.02, 0.40 TASKS: 1060 NODENAME: iop053063.lss.emc.com RELEASE: 3.10.0-957.el7.x86_64 VERSION: #1 SMP Thu Oct 4 20:48:51 UTC 2018 MACHINE: x86_64 (2999 Mhz) MEMORY: 127.9 GB PANIC: "SysRq : Trigger a crash" crash> set scope st_create set: gdb cannot find text block for address: st_create To find the correct symtab, let's check whether there is an address mapping to 'block' in the symtab searching loop and the PC is in the range. If the symtab associated with PC is found, and then use it. Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com&gt; --- gdb-7.6.patch | 38 +++++++++++++++++++++++++++++++++++++- 1 file changed, 37 insertions(+), 1 deletion(-) diff --git a/gdb-7.6.patch b/gdb-7.6.patch index f64b55fe547a..90629889f8c4 100644 --- a/gdb-7.6.patch +++ b/gdb-7.6.patch @@ -2500,4 +2500,40 @@ diff -up gdb-7.6/opcodes/configure.orig gdb-7.6/opcodes/configure +struct target_desc *tdesc_aarch64; #include "features/aarch64.c" #include "features/aarch64-without-fpu.c" - + +--- gdb-7.6/gdb/symtab.c.orig ++++ gdb-7.6/gdb/symtab.c +@@ -2065,7 +2065,7 @@ find_pc_sect_symtab (CORE_ADDR pc, struct obj_section *section) + struct symtab *s = NULL; + struct symtab *best_s = NULL; + struct objfile *objfile; +- CORE_ADDR distance = 0; ++ CORE_ADDR distance = 0, start, end; + struct minimal_symbol *msymbol; + + /* If we know that this is not a text address, return failure. This is +@@ -2102,10 +2102,20 @@ find_pc_sect_symtab (CORE_ADDR pc, struct obj_section *section) + bv = BLOCKVECTOR (s); + b = BLOCKVECTOR_BLOCK (bv, GLOBAL_BLOCK); + +- if (BLOCK_START (b) <= pc +- && BLOCK_END (b) > pc +- && (distance == 0 +- || BLOCK_END (b) - BLOCK_START (b) < distance)) ++ start = BLOCK_START (b); ++ end = BLOCK_END (b); ++ ++ /* ++ * If we have an addrmap mapping code addresses to blocks, and pc ++ * is in the range [start, end), let's use it. ++ */ ++ if ((pc >= start && pc < end) && BLOCKVECTOR_MAP (bv)) { ++ if (addrmap_find (BLOCKVECTOR_MAP (bv), pc)) ++ return s; ++ } ++ ++ if ((pc >= start && pc < end) && ((distance == 0) ++ || (end - start < distance))) + { + /* For an objfile that has its functions reordered, + find_pc_psymtab will find the proper partial symbol table -- 2.17.1 -- Crash-utility mailing list Crash-utility(a)redhat.com https://listman.redhat.com/mailman/listinfo/crash-utility