From cfc5e5040c93486323165196550dbe18aec46402 Mon Sep 17 00:00:00 2001 From: Aaron Plattner Date: Thu, 26 Dec 2019 13:40:17 -0800 Subject: [PATCH] modesetting: Check whether RandR was initialized before calling rrGetScrPriv MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Calling rrGetScrPriv when RandR isn't initialized causes an assertion failure that aborts the server: Xorg: ../include/privates.h:121: dixGetPrivateAddr: Assertion `key->initialized' failed. Thread 1 "Xorg" received signal SIGABRT, Aborted. 0x00007ffff78a8f25 in raise () from /usr/lib/libc.so.6 (gdb) bt #0 0x00007ffff78a8f25 in raise () from /usr/lib/libc.so.6 #1 0x00007ffff7892897 in abort () from /usr/lib/libc.so.6 #2 0x00007ffff7892767 in __assert_fail_base.cold () from /usr/lib/libc.so.6 #3 0x00007ffff78a1526 in __assert_fail () from /usr/lib/libc.so.6 #4 0x00007ffff7fb57c1 in dixGetPrivateAddr (privates=0x555555ab1b60, key=0x555555855720 ) at ../include/privates.h:121 #5 0x00007ffff7fb5822 in dixGetPrivate (privates=0x555555ab1b60, key=0x555555855720 ) at ../include/privates.h:136 #6 0x00007ffff7fb586a in dixLookupPrivate (privates=0x555555ab1b60, key=0x555555855720 ) at ../include/privates.h:166 #7 0x00007ffff7fb8445 in CreateScreenResources (pScreen=0x555555ab1790) at ../hw/xfree86/drivers/modesetting/driver.c:1335 #8 0x000055555576c5e4 in xf86CrtcCreateScreenResources (screen=0x555555ab1790) at ../hw/xfree86/modes/xf86Crtc.c:744 #9 0x00005555555d8bb6 in dix_main (argc=4, argv=0x7fffffffead8, envp=0x7fffffffeb00) at ../dix/main.c:214 #10 0x00005555557a4f0b in main (argc=4, argv=0x7fffffffead8, envp=0x7fffffffeb00) at ../dix/stubmain.c:34 This can happen, for example, if the server is configured with Xinerama and there is more than one X screen: Section "ServerLayout" Identifier "crash" Screen 0 "modesetting" Screen 1 "dummy" RightOf "modesetting" Option "Xinerama" EndSection Section "Device" Identifier "modesetting" Driver "modesetting" EndSection Section "Screen" Identifier "modesetting" Device "modesetting" EndSection Section "Device" Identifier "dummy" Driver "dummy" EndSection Section "Screen" Identifier "dummy" Device "dummy" EndSection The problem does not reproduce if there is only one X screen because of this code in xf86RandR12Init: #ifdef PANORAMIX /* XXX disable RandR when using Xinerama */ if (!noPanoramiXExtension) { if (xf86NumScreens == 1) noPanoramiXExtension = TRUE; else return TRUE; } #endif Fix the problem by checking dixPrivateKeyRegistered(rrPrivKey) before calling rrGetScrPriv. This is similar to what the xf86-video-amdgpu driver does: https://gitlab.freedesktop.org/xorg/driver/xf86-video-amdgpu/blob/fd66f5c0bea2b7c22a47bfd5eb1f22d32d166d9c/src/amdgpu_kms.c#L388 Signed-off-by: Aaron Plattner Reviewed-by: Michel Dänzer (cherry picked from commit 4226c6d0329df440551b7b91ae573a82c64a1ac9) --- hw/xfree86/drivers/modesetting/driver.c | 11 +++++++---- hw/xfree86/drivers/modesetting/drmmode_display.c | 8 +++++++- hw/xfree86/drivers/modesetting/vblank.c | 7 ++++++- 3 files changed, 20 insertions(+), 6 deletions(-) diff --git a/hw/xfree86/drivers/modesetting/driver.c b/hw/xfree86/drivers/modesetting/driver.c index 8d29b130f..9beb51f36 100644 --- a/hw/xfree86/drivers/modesetting/driver.c +++ b/hw/xfree86/drivers/modesetting/driver.c @@ -1332,7 +1332,6 @@ static Bool CreateScreenResources(ScreenPtr pScreen) { ScrnInfoPtr pScrn = xf86ScreenToScrn(pScreen); - rrScrPrivPtr pScrPriv = rrGetScrPriv(pScreen); modesettingPtr ms = modesettingPTR(pScrn); PixmapPtr rootPixmap; Bool ret; @@ -1398,10 +1397,14 @@ CreateScreenResources(ScreenPtr pScreen) } } - pScrPriv->rrEnableSharedPixmapFlipping = msEnableSharedPixmapFlipping; - pScrPriv->rrDisableSharedPixmapFlipping = msDisableSharedPixmapFlipping; + if (dixPrivateKeyRegistered(rrPrivKey)) { + rrScrPrivPtr pScrPriv = rrGetScrPriv(pScreen); - pScrPriv->rrStartFlippingPixmapTracking = msStartFlippingPixmapTracking; + pScrPriv->rrEnableSharedPixmapFlipping = msEnableSharedPixmapFlipping; + pScrPriv->rrDisableSharedPixmapFlipping = msDisableSharedPixmapFlipping; + + pScrPriv->rrStartFlippingPixmapTracking = msStartFlippingPixmapTracking; + } return ret; } diff --git a/hw/xfree86/drivers/modesetting/drmmode_display.c b/hw/xfree86/drivers/modesetting/drmmode_display.c index eca058258..e18cc379f 100644 --- a/hw/xfree86/drivers/modesetting/drmmode_display.c +++ b/hw/xfree86/drivers/modesetting/drmmode_display.c @@ -3226,13 +3226,19 @@ static void drmmode_validate_leases(ScrnInfoPtr scrn) { ScreenPtr screen = scrn->pScreen; - rrScrPrivPtr scr_priv = rrGetScrPriv(screen); + rrScrPrivPtr scr_priv; modesettingPtr ms = modesettingPTR(scrn); drmmode_ptr drmmode = &ms->drmmode; drmModeLesseeListPtr lessees; RRLeasePtr lease, next; int l; + /* Bail out if RandR wasn't initialized. */ + if (!dixPrivateKeyRegistered(rrPrivKey)) + return; + + scr_priv = rrGetScrPriv(screen); + /* We can't talk to the kernel about leases when VT switched */ if (!scrn->vtSema) return; diff --git a/hw/xfree86/drivers/modesetting/vblank.c b/hw/xfree86/drivers/modesetting/vblank.c index 31ff244ad..50d2fd3a4 100644 --- a/hw/xfree86/drivers/modesetting/vblank.c +++ b/hw/xfree86/drivers/modesetting/vblank.c @@ -220,7 +220,7 @@ static RRCrtcPtr ms_covering_randr_crtc(ScreenPtr pScreen, BoxPtr box, Bool screen_is_ms) { ScrnInfoPtr scrn = xf86ScreenToScrn(pScreen); - rrScrPrivPtr pScrPriv = rrGetScrPriv(pScreen); + rrScrPrivPtr pScrPriv; RRCrtcPtr crtc, best_crtc; int coverage, best_coverage; int c; @@ -230,6 +230,11 @@ ms_covering_randr_crtc(ScreenPtr pScreen, BoxPtr box, Bool screen_is_ms) best_crtc = NULL; best_coverage = 0; + if (!dixPrivateKeyRegistered(rrPrivKey)) + return NULL; + + pScrPriv = rrGetScrPriv(pScreen); + if (!pScrPriv) return NULL;