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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 199A621A5C X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Spamd-Result: default: False [-3.01 / 50.00]; BAYES_HAM(-3.00)[100.00%]; SUSPICIOUS_RECIPS(1.50)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_SHORT(-0.20)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; RBL_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:104:10:150:64:97:from]; FUZZY_RATELIMITED(0.00)[rspamd.com]; TO_DN_SOME(0.00)[]; FREEMAIL_TO(0.00)[gmail.com,linux.intel.com,kernel.org,ffwll.ch]; MIME_TRACE(0.00)[0:+]; ARC_NA(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; RCVD_TLS_ALL(0.00)[]; DKIM_TRACE(0.00)[suse.de:+]; RCVD_COUNT_TWO(0.00)[2]; DNSWL_BLOCKED(0.00)[2a07:de40:b281:104:10:150:64:97:from,2a07:de40:b281:106:10:150:64:167:received]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; SPAMHAUS_XBL(0.00)[2a07:de40:b281:104:10:150:64:97:from]; MID_RHS_MATCH_FROM(0.00)[]; RECEIVED_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:106:10:150:64:167:received]; RCPT_COUNT_SEVEN(0.00)[8]; RCVD_VIA_SMTP_AUTH(0.00)[]; TAGGED_RCPT(0.00)[147ba789658184f0ce04]; DBL_BLOCKED_OPENRESOLVER(0.00)[syzkaller.appspot.com:url,imap1.dmz-prg2.suse.org:helo,imap1.dmz-prg2.suse.org:rdns,appspotmail.com:email,suse.de:email,suse.de:mid,suse.de:dkim] X-Rspamd-Action: no action X-Spam-Flag: NO X-Spam-Score: -3.01 X-Spam-Level: Am 28.10.25 um 04:43 schrieb Chintan Patel: > Currently, wait_event_timeout() in drm_wait_one_vblank() uses a 100ms > timeout. Under heavy scheduling pressure or rare delayed vblank > handling, this can trigger WARNs unnecessarily. > > Increase the timeout to 1000ms to reduce spurious WARNs, while still > catching genuine issues. Thanks a lot. > > Reported-by: syzbot+147ba789658184f0ce04@syzkaller.appspotmail.com > Closes: https://syzkaller.appspot.com/bug?extid=147ba789658184f0ce04 > Tested-by: syzbot+147ba789658184f0ce04@syzkaller.appspotmail.com > Signed-off-by: Chintan Patel Reviewed-by: Thomas Zimmermann > > v2: > - Dropped unnecessary in-code comment (suggested by Thomas Zimmermann) > - Removed else branch, only log timeout case > > v3: > - Replaced drm_dbg_kms()/manual logging with drm_err() (suggested by Ville Syrjälä) > - Removed unnecessary curr = drm_vblank_count() (suggested by Thomas Zimmermann) > - Fixed commit message wording ("invalid userspace calls" → "delayed vblank handling") > > v4: > - Keep the original drm_WARN() to catch genuine kernel issues > - Increased timeout from 100ms → 1000ms to reduce spurious WARNs (suggested by Thomas Zimmermann) > --- > drivers/gpu/drm/drm_vblank.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c > index 46f59883183d..f779103b261b 100644 > --- a/drivers/gpu/drm/drm_vblank.c > +++ b/drivers/gpu/drm/drm_vblank.c > @@ -1303,7 +1303,7 @@ void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe) > > ret = wait_event_timeout(vblank->queue, > last != drm_vblank_count(dev, pipe), > - msecs_to_jiffies(100)); > + msecs_to_jiffies(1000)); > > drm_WARN(dev, ret == 0, "vblank wait timed out on crtc %i\n", pipe); > -- -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Frankenstrasse 146, 90461 Nuernberg, Germany GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman HRB 36809 (AG Nuernberg)