diff options
| author | mjg <mjg@FreeBSD.org> | 2017-12-31 02:48:16 +0000 |
|---|---|---|
| committer | Luiz Souza <luiz@netgate.com> | 2018-02-19 14:44:34 -0300 |
| commit | 457061d949ae73e58071fe42a7430d13af05e237 (patch) | |
| tree | e76c7e74c9d27da566321e985307c79420b8c7fb | |
| parent | ad10a4776f2fb0039e322a9e45c4a4746be66161 (diff) | |
| download | FreeBSD-src-457061d949ae73e58071fe42a7430d13af05e237.zip FreeBSD-src-457061d949ae73e58071fe42a7430d13af05e237.tar.gz | |
MFC r321922:
amd64: annotate the syscall return address check with __predict_false
before:
0xffffffff80b03ebb <+2059>: mov 0x460(%r14),%rax
0xffffffff80b03ec2 <+2066>: mov 0x98(%rax),%rax
0xffffffff80b03ec9 <+2073>: shr $0x2f,%rax
0xffffffff80b03ecd <+2077>: je 0xffffffff80b03edd <amd64_syscall+2093>
0xffffffff80b03ecf <+2079>: mov 0x3f8(%r14),%rax
0xffffffff80b03ed6 <+2086>: orl $0x1,0xc8(%rax)
0xffffffff80b03edd <+2093>: add $0xf8,%rsp
after:
0xffffffff80b03ebb <+2059>: mov 0x460(%r14),%rax
0xffffffff80b03ec2 <+2066>: mov 0x98(%rax),%rax
0xffffffff80b03ec9 <+2073>: shr $0x2f,%rax
0xffffffff80b03ecd <+2077>: jne 0xffffffff80b03eef <amd64_syscall+2111>
0xffffffff80b03ecf <+2079>: add $0xf8,%rsp
(cherry picked from commit 4ebdf0a463e767672045047ec82c75bf545e9a7c)
| -rw-r--r-- | sys/amd64/amd64/trap.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/sys/amd64/amd64/trap.c b/sys/amd64/amd64/trap.c index 070d722b..67c5868 100644 --- a/sys/amd64/amd64/trap.c +++ b/sys/amd64/amd64/trap.c @@ -933,6 +933,6 @@ amd64_syscall(struct thread *td, int traced) * not be safe. Instead, use the full return path which * catches the problem safely. */ - if (td->td_frame->tf_rip >= VM_MAXUSER_ADDRESS) + if (__predict_false(td->td_frame->tf_rip >= VM_MAXUSER_ADDRESS)) set_pcb_flags(td->td_pcb, PCB_FULL_IRET); } |
