Re: [PATCH 1/2] x86/mm: Give each mm a unique ID

[Tim Chen]

On 03/08/2018 10:23 AM, Tim Chen wrote:
> On 03/07/2018 09:30 AM, Greg Kroah-Hartman wrote:
>> On Fri, Mar 02, 2018 at 01:32:09PM -0800, Tim Chen wrote:
>>> From: Andy Lutomirski <luto@xxxxxxxxxx>
>>> commit: f39681ed0f48498b80455095376f11535feea332
>>>
>>> This adds a new variable to mmu_context_t: ctx_id.
>>> ctx_id uniquely identifies the mm_struct and will never be reused.
>>>
>>> Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
>>> Reviewed-by: Nadav Amit <nadav.amit@xxxxxxxxx>
>>> Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
>>> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
>>> Cc: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
>>> Cc: Borislav Petkov <bp@xxxxxxxxx>
>>> Cc: Dave Hansen <dave.hansen@xxxxxxxxx>
>>> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
>>> Cc: Mel Gorman <mgorman@xxxxxxx>
>>> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
>>> Cc: Rik van Riel <riel@xxxxxxxxxx>
>>> Cc: linux-mm@xxxxxxxxx
>>> Link: http://lkml.kernel.org/r/413a91c24dab3ed0caa5f4e4d017d87b0857f920.1498751203.git.luto@xxxxxxxxxx
>>> Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
>>> Signed-off-by: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx>
>>> ---
>>>  arch/x86/include/asm/mmu.h         | 15 +++++++++++++--
>>>  arch/x86/include/asm/mmu_context.h |  5 +++++
>>>  arch/x86/mm/tlb.c                  |  2 ++
>>>  3 files changed, 20 insertions(+), 2 deletions(-)
>>>
>>
>> Does not apply to 4.4.y :(
>>
>> Can you provide a working backport for that tree?
>>
> 
> Okay. Will do.  Thanks.
> 


Greg,

I actually found that there are a number of dependent IBPB related patches that haven't been
backported yet to 4.4:

    x86/cpufeatures: Add AMD feature bits for Speculation Control
    (cherry picked from commit 5d10cbc91d9eb5537998b65608441b592eec65e7)

    x86/msr: Add definitions for new speculation control MSRs
    (cherry picked from commit 1e340c60d0dd3ae07b5bedc16a0469c14b9f3410)

    x86/speculation: Add basic IBPB (Indirect Branch Prediction Barrier) support
    (cherry picked from commit 20ffa1caecca4db8f79fe665acdeaa5af815a24d)

    x86/cpufeatures: Clean up Spectre v2 related CPUID flags
    (cherry picked from commit 2961298efe1ea1b6fc0d7ee8b76018fa6c0bcef2)

And probably and a few more.
You have plans to backport these patches?

Tim