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| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2018-05-18 09:47:12 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-06-21 17:34:56 +0300 |
| commit | d31a580266eeb1f355df90fde8a71f480e30ad70 (patch) | |
| tree | cd4bbc37279a4f72257c8338c4051a441239d570 /tools/objtool | |
| parent | 0c414367c04eeb00c3ebfee0b74c9e7f3b95fd62 (diff) | |
| download | linux-d31a580266eeb1f355df90fde8a71f480e30ad70.tar.xz | |
x86/unwind/orc: Detect the end of the stack
The existing UNWIND_HINT_EMPTY annotations happen to be good indicators
of where entry code calls into C code for the first time. So also use
them to mark the end of the stack for the ORC unwinder.
Use that information to set unwind->error if the ORC unwinder doesn't
unwind all the way to the end. This will be needed for enabling
HAVE_RELIABLE_STACKTRACE for the ORC unwinder so we can use it with the
livepatch consistency model.
Thanks to Jiri Slaby for teaching the ORCs about the unwind hints.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/lkml/20180518064713.26440-5-jslaby@suse.cz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'tools/objtool')
| -rw-r--r-- | tools/objtool/arch/x86/include/asm/orc_types.h | 2 | ||||
| -rw-r--r-- | tools/objtool/check.c | 1 | ||||
| -rw-r--r-- | tools/objtool/check.h | 2 | ||||
| -rw-r--r-- | tools/objtool/orc_dump.c | 3 | ||||
| -rw-r--r-- | tools/objtool/orc_gen.c | 2 |
5 files changed, 8 insertions, 2 deletions
diff --git a/tools/objtool/arch/x86/include/asm/orc_types.h b/tools/objtool/arch/x86/include/asm/orc_types.h index 9c9dc579bd7d..46f516dd80ce 100644 --- a/tools/objtool/arch/x86/include/asm/orc_types.h +++ b/tools/objtool/arch/x86/include/asm/orc_types.h @@ -88,6 +88,7 @@ struct orc_entry { unsigned sp_reg:4; unsigned bp_reg:4; unsigned type:2; + unsigned end:1; } __packed; /* @@ -101,6 +102,7 @@ struct unwind_hint { s16 sp_offset; u8 sp_reg; u8 type; + u8 end; }; #endif /* __ASSEMBLY__ */ diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 38047c6aa575..8491beb1a636 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -1156,6 +1156,7 @@ static int read_unwind_hints(struct objtool_file *file) cfa->offset = hint->sp_offset; insn->state.type = hint->type; + insn->state.end = hint->end; } return 0; diff --git a/tools/objtool/check.h b/tools/objtool/check.h index c6b68fcb926f..95700a2bcb7c 100644 --- a/tools/objtool/check.h +++ b/tools/objtool/check.h @@ -31,7 +31,7 @@ struct insn_state { int stack_size; unsigned char type; bool bp_scratch; - bool drap; + bool drap, end; int drap_reg, drap_offset; struct cfi_reg vals[CFI_NUM_REGS]; }; diff --git a/tools/objtool/orc_dump.c b/tools/objtool/orc_dump.c index c3343820916a..faa444270ee3 100644 --- a/tools/objtool/orc_dump.c +++ b/tools/objtool/orc_dump.c @@ -203,7 +203,8 @@ int orc_dump(const char *_objname) print_reg(orc[i].bp_reg, orc[i].bp_offset); - printf(" type:%s\n", orc_type_name(orc[i].type)); + printf(" type:%s end:%d\n", + orc_type_name(orc[i].type), orc[i].end); } elf_end(elf); diff --git a/tools/objtool/orc_gen.c b/tools/objtool/orc_gen.c index 18384d9be4e1..3f98dcfbc177 100644 --- a/tools/objtool/orc_gen.c +++ b/tools/objtool/orc_gen.c @@ -31,6 +31,8 @@ int create_orc(struct objtool_file *file) struct cfi_reg *cfa = &insn->state.cfa; struct cfi_reg *bp = &insn->state.regs[CFI_BP]; + orc->end = insn->state.end; + if (cfa->base == CFI_UNDEFINED) { orc->sp_reg = ORC_REG_UNDEFINED; continue; |