From: Li Zhijian <lizhijian@fujitsu.com> stable inclusion from stable-v6.6.2 commit 41f3c9f024c83b8cd73a279a4492bbcd7cdbb034 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8IW7G Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 3531b27f1f04a6bc9c95cf00d40efe618d57aa93 ] Fix a missed "goto out" to unlock on error to cleanup this splat: WARNING: lock held when returning to user space! 6.6.0-rc3-lizhijian+ #213 Not tainted ------------------------------------------------ cxl/673 is leaving the kernel with locks still held! 1 lock held by cxl/673: #0: ffffffffa013b9d0 (cxl_region_rwsem){++++}-{3:3}, at: commit_store+0x7d/0x3e0 [cxl_core] In terms of user visible impact of this bug for backports: cxl_region_invalidate_memregion() on x86 invokes wbinvd which is a problematic instruction for virtualized environments. So, on virtualized x86, cxl_region_invalidate_memregion() returns an error. This failure case got missed because CXL memory-expander device passthrough is not a production use case, and emulation of CXL devices is typically limited to kernel development builds with CONFIG_CXL_REGION_INVALIDATION_TEST=y, that makes cxl_region_invalidate_memregion() succeed. In other words, the expected exposure of this bug is limited to CXL subsystem development environments using QEMU that neglected CONFIG_CXL_REGION_INVALIDATION_TEST=y. Fixes: d1257d098a5a ("cxl/region: Move cache invalidation before region teardown, and before setup") Signed-off-by: Li Zhijian <lizhijian@fujitsu.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/20231025085450.2514906-1-lizhijian@fujitsu.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- drivers/cxl/core/region.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c index 644032cd680e..d1f513800c10 100644 --- a/drivers/cxl/core/region.c +++ b/drivers/cxl/core/region.c @@ -288,7 +288,7 @@ static ssize_t commit_store(struct device *dev, struct device_attribute *attr, */ rc = cxl_region_invalidate_memregion(cxlr); if (rc) - return rc; + goto out; if (commit) { rc = cxl_region_decode_commit(cxlr); -- 2.25.1