lkml.org 
[lkml]   [2022]   [Oct]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRE: [PATCH 6/6] x86/gsseg: use the LKGS in struction if available for load gs index()
On October 7, 2022 11:07:34 AM PDT, "Li, Xin3" <xin3.li@intel.com> wrote:
>> >> + alternative_io("1: call asm_load_gs_index\n"
>> >> + ".pushsection \".fixup\",\"ax\"\n"
>> >> + "2: xorl %k[sel], %k[sel]\n"
>> >> + " jmp 1b\n"
>> >> + ".popsection\n"
>> >> + _ASM_EXTABLE(1b, 2b),
>> >> + _ASM_BYTES(0x3e) LKGS_DI,
>> >> + X86_FEATURE_LKGS,
>> >> + ASM_OUTPUT2([sel] "+D" (sel), ASM_CALL_CONSTRAINT),
>> >> + ASM_NO_INPUT_CLOBBER(_ASM_AX));
>> >> }
>> >
>> >I'm very sure none of this was tested... the .fixup section hasn't
>> >existed for almost a year now.
>> >
>> > e5eefda5aa51 ("x86: Remove .fixup section")
>>
>> Xin, what did you use as the forward-porting baseline?
>
>6.0 release, and my kernel dump shows me a fixup section is there, and a fixup section is created anyway if we do "pushsection "\.fixup\"".
>
>
>

Yeah. .fixup is really Just Another Text Section ™, so it is probably not surprising if it has crept back in.

\
 
 \ /
  Last update: 2022-10-07 20:50    [W:0.068 / U:0.508 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site