diff options
Diffstat (limited to 'common-user/host/x86_64/safe-syscall.inc.S')
| -rw-r--r-- | common-user/host/x86_64/safe-syscall.inc.S | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/common-user/host/x86_64/safe-syscall.inc.S b/common-user/host/x86_64/safe-syscall.inc.S index 84fed206f9..a20927a783 100644 --- a/common-user/host/x86_64/safe-syscall.inc.S +++ b/common-user/host/x86_64/safe-syscall.inc.S @@ -68,9 +68,18 @@ safe_syscall_start: jnz 2f syscall safe_syscall_end: + /* code path for having successfully executed the syscall */ +#if defined(__linux__) + /* Linux kernel returns (small) negative errno. */ cmp $-4095, %rax jae 0f +#elif defined(__FreeBSD__) + /* FreeBSD kernel returns positive errno and C bit set. */ + jc 1f +#else +#error "unsupported os" +#endif pop %rbp .cfi_remember_state .cfi_def_cfa_offset 8 @@ -78,8 +87,10 @@ safe_syscall_end: ret .cfi_restore_state +#if defined(__linux__) 0: neg %eax jmp 1f +#endif /* code path when we didn't execute the syscall */ 2: mov $QEMU_ERESTARTSYS, %eax |