mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-22 10:31:08 +00:00
Code Issues Releases Wiki Activity
linux-stable/drivers/nvdimm
History
Dan Williams a371788d4f cxl/pmem: Fix nvdimm registration races 
commit f57aec443c upstream.

A loop of the form:

    while true; do modprobe cxl_pci; modprobe -r cxl_pci; done

...fails with the following crash signature:

    BUG: kernel NULL pointer dereference, address: 0000000000000040
    [..]
    RIP: 0010:cxl_internal_send_cmd+0x5/0xb0 [cxl_core]
    [..]
    Call Trace:
     <TASK>
     cxl_pmem_ctl+0x121/0x240 [cxl_pmem]
     nvdimm_get_config_data+0xd6/0x1a0 [libnvdimm]
     nd_label_data_init+0x135/0x7e0 [libnvdimm]
     nvdimm_probe+0xd6/0x1c0 [libnvdimm]
     nvdimm_bus_probe+0x7a/0x1e0 [libnvdimm]
     really_probe+0xde/0x380
     __driver_probe_device+0x78/0x170
     driver_probe_device+0x1f/0x90
     __device_attach_driver+0x85/0x110
     bus_for_each_drv+0x7d/0xc0
     __device_attach+0xb4/0x1e0
     bus_probe_device+0x9f/0xc0
     device_add+0x445/0x9c0
     nd_async_device_register+0xe/0x40 [libnvdimm]
     async_run_entry_fn+0x30/0x130

...namely that the bottom half of async nvdimm device registration runs
after the CXL has already torn down the context that cxl_pmem_ctl()
needs. Unlike the ACPI NFIT case that benefits from launching multiple
nvdimm device registrations in parallel from those listed in the table,
CXL is already marked PROBE_PREFER_ASYNCHRONOUS. So provide for a
synchronous registration path to preclude this scenario.

Fixes: 21083f5152 ("cxl/pmem: Register 'pmem' / cxl_nvdimm devices")
Cc: <stable@vger.kernel.org>
Reported-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-10 09:34:20 +01:00
..
badrange.c
btt.c
btt.h
btt_devs.c
bus.c cxl/pmem: Fix nvdimm registration races 2023-03-10 09:34:20 +01:00
claim.c
core.c
dax_devs.c
dimm.c
dimm_devs.c cxl/pmem: Fix nvdimm registration races 2023-03-10 09:34:20 +01:00
e820.c
Kconfig nvdimm: Support sizeof(struct page) > MAX_STRUCT_PAGE_SIZE 2023-02-14 19:11:53 +01:00
label.c
label.h
Makefile
namespace_devs.c libnvdimm for 6.1 2022-10-14 18:41:41 -07:00
nd-core.h cxl/pmem: Fix nvdimm registration races 2023-03-10 09:34:20 +01:00
nd.h nvdimm: Support sizeof(struct page) > MAX_STRUCT_PAGE_SIZE 2023-02-14 19:11:53 +01:00
nd_perf.c
nd_virtio.c
of_pmem.c
pfn.h
pfn_devs.c nvdimm: Support sizeof(struct page) > MAX_STRUCT_PAGE_SIZE 2023-02-14 19:11:53 +01:00
pmem.c Merge branch 'for-6.0/dax' into libnvdimm-fixes 2022-09-24 18:14:12 -07:00
pmem.h
region.c
region_devs.c libnvdimm/region: Allow setting align attribute on regions without mappings 2022-09-29 17:22:30 -07:00
security.c nvdimm: make __nvdimm_security_overwrite_query static 2022-09-20 10:23:52 -07:00
virtio_pmem.c virtio_pmem: set device ready in probe() 2022-08-11 04:06:37 -04:00
virtio_pmem.h