Re: [Qemu-devel] [PULL 0/4] tlb fixes for self-modifying code

Re: [Qemu-devel] [PULL 0/4] tlb fixes for self-modifying code

[Hulin, Patrick - 0559 - MITLL]

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Hi all,

 

Just noticed this patch and wanted to leave a quick comment. The original
issue wasn't with cross-page writes - it was with cross-TB writes.
Cross-page writes become an issue once you reverse the order of the loop, so
that part of the patch is necessary. But someone might want to leave a note
in the code that there's still an issue when doing an unaligned write off
the front of a TB. The  patch fixes the behavior of vanilla Windows 7 x64,
which is definitely an improvement, but there are a few real applications
that break it. (Photoshop is one, I believe).

 

-Patrick


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Re: [Qemu-devel] [PULL 0/4] tlb fixes for self-modifying code

[Peter Maydell]

On 8 July 2016 at 21:38, Richard Henderson <rth@twiddle.net> wrote:
> Synchronicity?  Both changes look good to me.
>
> I took the opportunity to tidy up softmmu_template.h a tiny bit at
> the same time, to avoid too much increase in code size in cold code
> paths.  The final is 4k smaller than the original.
>
>
> r~
>
>
> The following changes since commit 4f4a9ca4a4386c137301b3662faba076455ff15a:
>
>   Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20160707' into staging (2016-07-07 14:49:38 +0100)
>
> are available in the git repository at:
>
>   git://github.com/rth7680/qemu.git tags/pull-tcg-20160708
>
> for you to fetch changes up to 7399a337e4126f7c8c8af3336726f001378c4798:
>
>   translate-all: Fix user-mode self-modifying code in 2 page long TB (2016-07-08 13:17:38 -0700)
>
> ----------------------------------------------------------------
> two self-modifying code fixes
>

Applied, thanks.

-- PMM

[Qemu-devel] [PULL 0/4] tlb fixes for self-modifying code

[Richard Henderson]

Synchronicity?  Both changes look good to me.

I took the opportunity to tidy up softmmu_template.h a tiny bit at
the same time, to avoid too much increase in code size in cold code
paths.  The final is 4k smaller than the original.


r~


The following changes since commit 4f4a9ca4a4386c137301b3662faba076455ff15a:

  Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20160707' into staging (2016-07-07 14:49:38 +0100)

are available in the git repository at:

  git://github.com/rth7680/qemu.git tags/pull-tcg-20160708

for you to fetch changes up to 7399a337e4126f7c8c8af3336726f001378c4798:

  translate-all: Fix user-mode self-modifying code in 2 page long TB (2016-07-08 13:17:38 -0700)

----------------------------------------------------------------
two self-modifying code fixes

----------------------------------------------------------------
Richard Henderson (1):
      cputlb: Move VICTIM_TLB_HIT out of line

Samuel Damashek (2):
      cputlb: Add address parameter to VICTIM_TLB_HIT
      cputlb: Fix for self-modifying writes across page boundaries

Stanislav Shmarov (1):
      translate-all: Fix user-mode self-modifying code in 2 page long TB

 cputlb.c           | 29 ++++++++++++++++++++
 softmmu_template.h | 79 +++++++++++++++++++++++++++---------------------------
 translate-all.c    | 10 +++----
 3 files changed, 74 insertions(+), 44 deletions(-)