lkml.org 
[lkml]   [2018]   [Mar]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] KVM: X86: Fix the decoding of segment overrides in 64bit mode
From
Date
On 22/03/2018 11:19, Andrew Cooper wrote:
> On 22/03/2018 10:07, Paolo Bonzini wrote:
>> On 22/03/2018 09:34, Wanpeng Li wrote:
>>> From: Wanpeng Li <wanpengli@tencent.com>
>>>
>>> Explicit segment overides other than %fs and %gs are documented as ignored by
>>> both Intel and AMD.
>>>
>>> In practice, this means that:
>>>
>>> * Explicit uses of %ss don't actually yield #SS[0] for non-canonical
>>> memory references.
>>> * Explicit uses of %{e,c,d}s don't override %rbp/%rsp-based memory references
>>> to yield #GP[0] for non-canonical memory references.
>>>
>>> Cc: Paolo Bonzini <pbonzini@redhat.com>
>>> Cc: Radim Krčmář <rkrcmar@redhat.com>
>>> Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
>
> When porting fixes from other projects, it is customary to identify so
> in the commit message.  In this case, the fix you've ported is
> http://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=b7dce29d9faf3597d009c853ed1fcbed9f7a7f68
>
> Here is an example of how Xen ports fixes from Linux for the drivers
> that we share. 
> http://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=4e131596f1defec9407b6e60d584a696beaf5d7e

Thanks Andrew. The code is of course completely different, but the
commit message is 1:1. Wanpeng, please acknowledge Jan in v2!

>> Testcase, please...
>
> If you want to crib from one, this is the testcase I made for Xen.
>
> http://xenbits.xen.org/docs/xtf/test-memop-seg.html

How does it ensure that the code is executed through the emulator and
not by the processor?

> With the impending KVM/PVH work which is ongoing, it will soon be easy
> to run Xen's HVM test suite unmodified under KVM, but we're not quite
> there yet.

What does the test suite use for console I/O?

Paolo

\
 
 \ /
  Last update: 2018-03-22 11:46    [W:0.093 / U:0.328 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site