diff options
| author | Austin Clements <austin@google.com> | 2016-05-25 20:56:56 -0400 |
|---|---|---|
| committer | Austin Clements <austin@google.com> | 2016-05-26 13:54:05 +0000 |
| commit | b92f4238790c590168e7dae03165d75deb89fe41 (patch) | |
| tree | 54d3adc497c61e4857f37f6411ea65070fd012b9 /src | |
| parent | adff422779709c83db91700fdcc0a0bd5dee6a21 (diff) | |
| download | go-b92f4238790c590168e7dae03165d75deb89fe41.tar.xz | |
runtime: unwind BP in jmpdefer to match SP unwind
The irregular calling convention for defers currently incorrectly
manages the BP if frame pointers are enabled. Specifically, jmpdefer
manipulates the SP as if its own caller, deferreturn, had returned.
However, it does not manipulate the BP to match. As a result, when a
BP-based traceback happens during a deferred function call, it unwinds
to the function that performed the defer and then thinks that function
called itself in an infinite regress.
Fix this by making jmpdefer manipulate the BP as if deferreturn had
actually returned.
Fixes #12968.
Updates #15840.
Change-Id: Ic9cc7c863baeaf977883ed0c25a7e80e592cf066
Reviewed-on: https://go-review.googlesource.com/23457
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Diffstat (limited to 'src')
| -rw-r--r-- | src/runtime/asm_amd64.s | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/src/runtime/asm_amd64.s b/src/runtime/asm_amd64.s index d6e5494180..e50c443044 100644 --- a/src/runtime/asm_amd64.s +++ b/src/runtime/asm_amd64.s @@ -526,6 +526,7 @@ TEXT runtime·jmpdefer(SB), NOSPLIT, $0-16 MOVQ fv+0(FP), DX // fn MOVQ argp+8(FP), BX // caller sp LEAQ -8(BX), SP // caller sp after CALL + MOVQ -8(SP), BP // restore BP as if deferreturn returned (harmless if framepointers not in use) SUBQ $5, (SP) // return to CALL again MOVQ 0(DX), BX JMP BX // but first run the deferred function |