This is a note to let you know that I've just added the patch titled cxl/region: Fix region HPA ordering validation to the 6.0-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: cxl-region-fix-region-hpa-ordering-validation.patch and it can be found in the queue-6.0 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From a90accb358ae33ea982a35595573f7a045993f8b Mon Sep 17 00:00:00 2001 From: Dan Williams <dan.j.williams@xxxxxxxxx> Date: Thu, 3 Nov 2022 17:30:24 -0700 Subject: cxl/region: Fix region HPA ordering validation From: Dan Williams <dan.j.williams@xxxxxxxxx> commit a90accb358ae33ea982a35595573f7a045993f8b upstream. Some regions may not have any address space allocated. Skip them when validating HPA order otherwise a crash like the following may result: devm_cxl_add_region: cxl_acpi cxl_acpi.0: decoder3.4: created region9 BUG: kernel NULL pointer dereference, address: 0000000000000000 [..] RIP: 0010:store_targetN+0x655/0x1740 [cxl_core] [..] Call Trace: <TASK> kernfs_fop_write_iter+0x144/0x200 vfs_write+0x24a/0x4d0 ksys_write+0x69/0xf0 do_syscall_64+0x3a/0x90 store_targetN+0x655/0x1740: alloc_region_ref at drivers/cxl/core/region.c:676 (inlined by) cxl_port_attach_region at drivers/cxl/core/region.c:850 (inlined by) cxl_region_attach at drivers/cxl/core/region.c:1290 (inlined by) attach_target at drivers/cxl/core/region.c:1410 (inlined by) store_targetN at drivers/cxl/core/region.c:1453 Cc: <stable@xxxxxxxxxxxxxxx> Fixes: 384e624bb211 ("cxl/region: Attach endpoint decoders") Reviewed-by: Vishal Verma <vishal.l.verma@xxxxxxxxx> Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx> Link: https://lore.kernel.org/r/166752182461.947915.497032805239915067.stgit@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/cxl/core/region.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/cxl/core/region.c +++ b/drivers/cxl/core/region.c @@ -657,6 +657,9 @@ static struct cxl_region_ref *alloc_regi xa_for_each(&port->regions, index, iter) { struct cxl_region_params *ip = &iter->region->params; + if (!ip->res) + continue; + if (ip->res->start > p->res->start) { dev_dbg(&cxlr->dev, "%s: HPA order violation %s:%pr vs %pr\n", Patches currently in stable-queue which might be from dan.j.williams@xxxxxxxxx are queue-6.0/cxl-region-fix-distance-calculation-with-passthrough-ports.patch queue-6.0/acpi-numa-add-cxl-cfmws-nodes-to-the-possible-nodes-set.patch queue-6.0/cxl-region-fix-decoder-allocation-crash.patch queue-6.0/cxl-pmem-fix-cxl_pmem_region-and-cxl_memdev-leak.patch queue-6.0/cxl-region-fix-region-hpa-ordering-validation.patch queue-6.0/cxl-region-fix-cxl_region-leak-cleanup-targets-at-region-delete.patch