Bug#896979: xserver-xorg-video-nouveau: Crash when undocking Lenovo P50
On 2018-06-06 15:48 +0200, Michel Dänzer wrote:
> On 2018-06-06 03:05 PM, Sam Morris wrote:
>> Source: xserver-xorg-video-nouveau
>> Followup-For: Bug #896979
>>
>> I'm still seeing this with Xorg 1.20 (which is not unexpected). Here's a
>> better backtrace:
>>
>> #0 0x00007fd90edb5e7b in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51
>> #1 0x00007fd90edb7231 in __GI_abort () at abort.c:79
>> #2 0x0000557576dc55ca in OsAbort () at ../../../../os/utils.c:1350
>> #3 0x0000557576dcb163 in AbortServer () at ../../../../os/log.c:877
>> #4 0x0000557576dcbf85 in FatalError (f=f@entry=0x557576dfec30 "Caught signal %d (%s). Server aborting\n") at ../../../../os/log.c:1015
>> #5 0x0000557576dc26b3 in OsSigHandler (signo=11, sip=<optimized out>, unused=<optimized out>) at ../../../../os/osinit.c:156
>> #6 0x00007fd90f14cf50 in <signal handler called> () at /lib/x86_64-linux-gnu/libpthread.so.0
>> #7 0x00007fd90c027f29 in drmmode_output_dpms (output=0x557578bfaf20, mode=3) at ../../src/drmmode_display.c:921
>> #8 0x0000557576cd8813 in xf86DisableUnusedFunctions (pScrn=0x557578a6a120) at ../../../../../../hw/xfree86/modes/xf86Crtc.c:3021
>> #9 0x0000557576ce0980 in xf86RandR12CrtcSet (pScreen=<optimized out>, randr_crtc=0x557578c33220, randr_mode=0x0, x=0, y=0, rotation=<optimized out>, num_randr_outputs=0, randr_outputs=0x0) at ../../../../../../hw/xfree86/modes/xf86RandR12.c:1241
>> #10 0x0000557576d20122 in RRCrtcSet (crtc=<optimized out>, mode=0x0, x=0, y=0, rotation=rotation@entry=1, numOutputs=numOutputs@entry=0, outputs=0x0) at ../../../../randr/rrcrtc.c:774
>> #11 0x0000557576d219fe in ProcRRSetCrtcConfig (client=0x557578a598f0) at ../../../../randr/rrcrtc.c:1401
>> #12 0x0000557576c660b8 in Dispatch () at ../../../../dix/dispatch.c:478
>> #13 0x0000557576c6a0b8 in dix_main (argc=13, argv=0x7ffd47296448, envp=<optimized out>) at ../../../../dix/main.c:276
>> #14 0x00007fd90eda2a87 in __libc_start_main (main=0x557576c53d80 <main>, argc=13, argv=0x7ffd47296448, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffd47296438) at ../csu/libc-start.c:310
>> #15 0x0000557576c53dba in _start ()
>>
>> (gdb) frame 7
>> #7 drmmode_output_dpms (output=0x557578bfaf20, mode=3) at ../../src/drmmode_display.c:921
>> 921 in ../../src/drmmode_display.c
>>
>> Looking at that file in nouveau's source code:
>>
>> static void
>> drmmode_output_dpms(xf86OutputPtr output, int mode)
>> {
>> drmmode_output_private_ptr drmmode_output = output->driver_private;
>> drmModeConnectorPtr koutput = drmmode_output->mode_output;
>> drmModePropertyPtr props;
>> drmmode_ptr drmmode = drmmode_output->drmmode;
>> int mode_id = -1, i;
>>
>> for (i = 0; i < koutput->count_props; i++) { // <-- this line!
>> props = drmModeGetProperty(drmmode->fd, koutput->props[i]);
>> if (props && (props->flags & DRM_MODE_PROP_ENUM)) {
>> if (!strcmp(props->name, "DPMS")) {
>> mode_id = koutput->props[i];
>> drmModeFreeProperty(props);
>> break;
>> }
>> drmModeFreeProperty(props);
>> }
>> }
>>
>> Examining some variables:
>>
>> (gdb) p i
>> $7 = 0
>>
>> (gdb) p koutput
>> $8 = (struct _drmModeConnector *) 0x0
>
> Looks like the nouveau driver needs something like
>
> https://cgit.freedesktop.org/xorg/driver/xf86-video-amdgpu/commit/?id=f4107f67f147e2500582fc36cf0f0f76bc1ef098
Sam, could you please test the attached patch?
TIA,
Sven
>From f3ba56e9adf8ed96642b70ec5cf50234a98ab23b Mon Sep 17 00:00:00 2001
From: Sven Joachim <svenjoac@gmx.de>
Date: Wed, 6 Jun 2018 19:43:31 +0200
Subject: [PATCH] Check for NULL koutput in drmmode_output_dpms
---
src/drmmode_display.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/src/drmmode_display.c b/src/drmmode_display.c
index 2b71c9c4..9900674c 100644
--- a/src/drmmode_display.c
+++ b/src/drmmode_display.c
@@ -918,6 +918,9 @@ drmmode_output_dpms(xf86OutputPtr output, int mode)
drmmode_ptr drmmode = drmmode_output->drmmode;
int mode_id = -1, i;
+ if (!koutput)
+ return;
+
for (i = 0; i < koutput->count_props; i++) {
props = drmModeGetProperty(drmmode->fd, koutput->props[i]);
if (props && (props->flags & DRM_MODE_PROP_ENUM)) {
--
2.17.1
Reply to: