Re: [tip:x86/vdso] x86/vdso32/syscall.S: Do not load __USER32_DS to %ss

From: Borislav Petkov
Date: Thu Apr 23 2015 - 06:44:17 EST


On Thu, Apr 23, 2015 at 12:26:43PM +0200, Denys Vlasenko wrote:
> Yes. It loads *selector*. AMD docs say that selector is loaded as you say,
> but *cached descriptor* of SS (which is a different entity) is not modified.
>
> If *cached descriptor* is invalid, in 32-bit mode stack ops
> will fail. (In 64-bit mode, CPU doesn't do those checks).

So how can that happen with wine? Something's changing the cached
descriptor and only the write to %ss reloads it with the correct value?

--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.
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