Messages in this thread | | | Subject | Re: [PATCH 13/18] x86 vDSO: ia32 sysenter_return | From | Zachary Amsden <> | Date | Tue, 20 Nov 2007 16:05:34 -0800 |
| |
On Mon, 2007-11-19 at 14:06 -0800, Roland McGrath wrote: > This changes the 64-bit kernel's support for the 32-bit sysenter > instruction to use stored fields rather than constants for the > user-mode return address, as the 32-bit kernel does. This adds a > sysenter_return field to struct thread_info, as 32-bit has. There > is no observable effect from this yet. It makes the assembly code > independent of the 32-bit vDSO mapping address, paving the way for > making the vDSO address vary as it does on the 32-bit kernel.
I hope you won't carry the dependency of COMPAT_VDSO over to 64-bit when that happens.
> @@ -104,7 +103,7 @@ ENTRY(ia32_sysenter_target) > pushfq > CFI_ADJUST_CFA_OFFSET 8 > /*CFI_REL_OFFSET rflags,0*/ > - movl $VSYSCALL32_SYSEXIT, %r10d > + movl 8*3-THREAD_SIZE+threadinfo_sysenter_return(%rsp), %r10d
8*3-THREAD_SIZE is not very intuitive. Can you add a comment on the math?
Zach
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |