Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1211643

Re: [PATCH v2] x86/entry/32: Remove duplicate initialization of tss.ss1

From Andy Lutomirski <luto@amacapital.net>
Newsgroups linux.kernel
Subject Re: [PATCH v2] x86/entry/32: Remove duplicate initialization of tss.ss1
Date 2015-08-23 17:50 +0200
Message-ID <q0FGV-54n-11@gated-at.bofh.it> (permalink)
References <pPuc9-7rK-3@gated-at.bofh.it> <pPuc9-7rK-1@gated-at.bofh.it> <q0BDk-7OP-19@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On Sun, Aug 23, 2015 at 4:26 AM, Ingo Molnar <mingo@kernel.org> wrote:
>
> * Andy Lutomirski <luto@kernel.org> wrote:
>
>> It's statically initialized, so we don't need to dynamically
>> initialize it too.
>>
>> Reported-by: Brian Gerst <brgerst@gmail.com>
>> Signed-off-by: Andy Lutomirski <luto@kernel.org>
>> ---
>>
>> Changes since v1: Delete the code :)
>>
>> arch/x86/kernel/cpu/common.c | 8 --------
>>  1 file changed, 8 deletions(-)
>>
>> diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
>> index e2ed2513a51e..e08eee98a5f8 100644
>> --- a/arch/x86/kernel/cpu/common.c
>> +++ b/arch/x86/kernel/cpu/common.c
>> @@ -1005,14 +1005,6 @@ void enable_sep_cpu(void)
>>       if (IS_ENABLED(CONFIG_X86_32) && !boot_cpu_has(X86_FEATURE_SEP))
>>               goto out;
>>
>> -#ifdef CONFIG_X86_32
>> -     /*
>> -      * We cache MSR_IA32_SYSENTER_CS's value in the TSS's ss1 field --
>> -      * see the big comment in struct x86_hw_tss's definition.
>> -      */
>> -     tss->x86_tss.ss1 = __KERNEL_CS;
>> -#endif
>> -
>>       wrmsrl_safe(MSR_IA32_SYSENTER_CS, __KERNEL_CS);
>>       wrmsrl_safe(MSR_IA32_SYSENTER_ESP,
>>                   (unsigned long)tss +
>
> So this code changed substantially in tip:x86/asm - do we still need this patch?
>

Yes, although I think it's actually the other way around -- I think
this patch may have applied on top of something that never made it
into tip/x86/asm.  I can re-check or I could just rebase the patch (or
you could apply it with the obvious fixup).

It's obviously not a critical fix.

--Andy
--
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/

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

Re: [PATCH v2] x86/entry/32: Remove duplicate initialization of  tss.ss1 Ingo Molnar <mingo@kernel.org> - 2015-08-23 13:30 +0200
  Re: [PATCH v2] x86/entry/32: Remove duplicate initialization of tss.ss1 Andy Lutomirski <luto@amacapital.net> - 2015-08-23 17:50 +0200
    Re: [PATCH v2] x86/entry/32: Remove duplicate initialization of  tss.ss1 Ingo Molnar <mingo@kernel.org> - 2015-08-24 08:50 +0200

csiph-web