Dan Williams 7c7371b41a cxl/mem: Fix shutdown order ... [ Upstream commit 88d3917f82 ] Ira reports that removing cxl_mock_mem causes a crash with the following trace: BUG: kernel NULL pointer dereference, address: 0000000000000044 [..] RIP: 0010:cxl_region_decode_reset+0x7f/0x180 [cxl_core] [..] Call Trace: <TASK> cxl_region_detach+0xe8/0x210 [cxl_core] cxl_decoder_kill_region+0x27/0x40 [cxl_core] cxld_unregister+0x29/0x40 [cxl_core] devres_release_all+0xb8/0x110 device_unbind_cleanup+0xe/0x70 device_release_driver_internal+0x1d2/0x210 bus_remove_device+0xd7/0x150 device_del+0x155/0x3e0 device_unregister+0x13/0x60 devm_release_action+0x4d/0x90 ? __pfx_unregister_port+0x10/0x10 [cxl_core] delete_endpoint+0x121/0x130 [cxl_core] devres_release_all+0xb8/0x110 device_unbind_cleanup+0xe/0x70 device_release_driver_internal+0x1d2/0x210 bus_remove_device+0xd7/0x150 device_del+0x155/0x3e0 ? lock_release+0x142/0x290 cdev_device_del+0x15/0x50 cxl_memdev_unregister+0x54/0x70 [cxl_core] This crash is due to the clearing out the cxl_memdev's driver context (@cxlds) before the subsystem is done with it. This is ultimately due to the region(s), that this memdev is a member, being torn down and expecting to be able to de-reference @cxlds, like here: static int cxl_region_decode_reset(struct cxl_region *cxlr, int count) ... if (cxlds->rcd) goto endpoint_reset; ... Fix it by keeping the driver context valid until memdev-device unregistration, and subsequently the entire stack of related dependencies, unwinds. Fixes: 9cc238c7a5 ("cxl/pci: Introduce cdevm_file_operations") Reported-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Tested-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>		2023-11-20 11:52:13 +01:00
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core	cxl/mem: Fix shutdown order	2023-11-20 11:52:13 +01:00
acpi.c	cxl/acpi: Return 'rc' instead of '0' in cxl_parse_cfmws()	2023-08-03 10:24:04 +02:00
cxl.h	cxl/region: Fix 'distance' calculation with passthrough ports	2022-11-04 16:01:24 -07:00
cxlmem.h	cxl/region: Attach endpoint decoders	2022-07-25 12:18:07 -07:00
cxlpci.h	cxl: Wait Memory_Info_Valid before access memory related info	2023-05-30 14:03:32 +01:00
Kconfig	cxl/region: Allocate HPA capacity to regions	2022-07-25 12:18:06 -07:00
Makefile	PM: CXL: Disable suspend	2022-04-22 16:09:42 -07:00
mem.c	cxl/mem: Enumerate port targets before adding endpoints	2022-07-21 17:19:25 -07:00
pci.c	cxl/pci: Create PCI DOE mailbox's for memory devices	2022-07-19 15:38:04 -07:00
pmem.c	cxl/pmem: Fix nvdimm registration races	2023-03-10 09:34:20 +01:00
port.c	cxl/port: Read CDAT table	2022-07-19 15:38:05 -07:00