On Tue, 26 Aug 2025, Zheng Qixing wrote: > From: Zheng Qixing <zhengqixing@xxxxxxxxxx> > > Hello, > > During reliability testing of the dm module, we discovered two bugs when > performing create/remove and suspend/resume operations at high frequency. > > Analysis revealed that race conditions between suspend and table load > operations cause asymmetric handling of q->quiesce_depth and null pointer > dereference issues with q->tag_set. > > To address the q->tag_set null pointer issue, patch 2 determines whether > to perform certain suspend actions for request-based devices based on the > existence of the table (map). > > For detailed information, please refer to the patch commits. > > Additionally, since modern Linux kernels have indeed transitioned to > multi-queue as the default (and single-queue is largely deprecated), > is using queue_is_mq() to determine dm_request_based() obsolete? > > Zheng Qixing (2): > dm: fix queue start/stop imbalance under suspend/load/resume races > dm: fix NULL pointer dereference in __dm_suspend() > > drivers/md/dm-core.h | 1 + > drivers/md/dm.c | 13 ++++++++----- > 2 files changed, 9 insertions(+), 5 deletions(-) > > -- > 2.39.2 Both patches applied, thanks. Mikulas
