Attachment 144685 Details for Bug 99781 – Requested patch (does not work)

[patch] Requested patch (does not work)

0001-glx-Fix-synthetic-error-generation-in-__glXSendError.patch (text/plain), 2.07 KB, created by Hal Gentz on 2019-06-30 06:50:51 UTC

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Creator: Hal Gentz

Created: 2019-06-30 06:50:51 UTC

Size: 2.07 KB

patch

obsolete

>From 233d534c9fc65e64d718ac2a7274886fe7cfafe6 Mon Sep 17 00:00:00 2001
>From: Hal Gentz <zegentzy@protonmail.com>
>Date: Thu, 27 Jun 2019 17:50:54 -0600
>Subject: [PATCH] glx: Fix synthetic error generation in __glXSendError
>
>To quote Uli Schlachter, who understands this stuff more than I do:
>
>>   The function __glXSendError() in mesa's src/glx/glx_error.c invents an X11
>> protocol error out of thin air. For the sequence number it uses dpy->request.
>> This is the sequence number of the last request that was sent. _XError() will
>> then update dpy->last_request_read based on the sequence number of the error
>> that just "came in".
>>
>>   If now another something comes in with a sequence number less than
>> dpy->last_request_read, since sequence numbers are monotonically increasing,
>> widen() will incorrectly add 1<<32 to the sequence number and things might go
>> downhill afterwards.
>
>> [Adding] a call to XSync(dpy, False) to the "invent an error"-functions [...]
>> should guarantee that dpy->request == dpy->last_request_read and so it does
>> not matter any more which of the two sequence numbers mesa uses.
>
>`__glXSendErrorForXcb` was also patched, as that's the function that
>`glXCreateContextAttribsARB` actually uses.
>
>Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99781
>Cc: mesa-stable@lists.freedesktop.org
>Fixes: ad503c41 'apple: Initial import of libGL for OSX from AppleSGLX svn repository'
>Signed-off-by: Hal Gentz <zegentzy@protonmail.com>
>---
> src/glx/glx_error.c | 2 ++
> 1 file changed, 2 insertions(+)
>
>diff --git a/src/glx/glx_error.c b/src/glx/glx_error.c
>index 653cbeb2d2a..905290f5b7b 100644
>--- a/src/glx/glx_error.c
>+++ b/src/glx/glx_error.c
>@@ -60,6 +60,7 @@ __glXSendError(Display * dpy, int_fast8_t errorCode, uint_fast32_t resourceID,
>    error.majorCode = glx_dpy->majorOpcode;
> 
>    _XError(dpy, &error);
>+   XSync(dpy, False);
> 
>    UnlockDisplay(dpy);
> }
>@@ -79,6 +80,7 @@ __glXSendErrorForXcb(Display * dpy, const xcb_generic_error_t *err)
>    error.majorCode = err->major_code;
> 
>    _XError(dpy, &error);
>+   XSync(dpy, False);
> 
>    UnlockDisplay(dpy);
> }
>-- 
>2.22.0
>

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Attachments on bug 99781: 143763 | 143764 | 143765 | 143766 | 143767 | 144685

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