From 8c251c5ab1b7cd204231e4ee936bfe078a33f234 Mon Sep 17 00:00:00 2001 From: Li Ming Date: Fri, 9 Aug 2024 08:27:49 +0000 Subject: [PATCH 1/2] cxl/pci: Get AER capability address from RCRB only for RCH dport cxl_setup_parent_dport() needs to get RCH dport AER capability address from RCRB to disable AER interrupt. The function does not check if dport is RCH dport, it will get a wrong pci_host_bridge structure by dport_dev in VH case because dport_dev points to a pci device(RP or switch DSP) rather than a pci host bridge device. Fixes: f05fd10d138d ("cxl/pci: Add RCH downstream port AER register discovery") Signed-off-by: Li Ming Reviewed-by: Dan Williams Reviewed-by: Ira Weiny Tested-by: Ira Weiny Tested-by: Alison Schofield Link: https://patch.msgid.link/20240809082750.3015641-2-ming4.li@intel.com Signed-off-by: Dave Jiang --- drivers/cxl/core/pci.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c index a663e7566c480..51132a575b276 100644 --- a/drivers/cxl/core/pci.c +++ b/drivers/cxl/core/pci.c @@ -834,11 +834,13 @@ static void cxl_disable_rch_root_ints(struct cxl_dport *dport) void cxl_setup_parent_dport(struct device *host, struct cxl_dport *dport) { struct device *dport_dev = dport->dport_dev; - struct pci_host_bridge *host_bridge; - host_bridge = to_pci_host_bridge(dport_dev); - if (host_bridge->native_aer) - dport->rcrb.aer_cap = cxl_rcrb_to_aer(dport_dev, dport->rcrb.base); + if (dport->rch) { + struct pci_host_bridge *host_bridge = to_pci_host_bridge(dport_dev); + + if (host_bridge->native_aer) + dport->rcrb.aer_cap = cxl_rcrb_to_aer(dport_dev, dport->rcrb.base); + } dport->reg_map.host = host; cxl_dport_map_regs(dport); From 2c402bd2e85b44dc00ef85b5c0e217de684b5372 Mon Sep 17 00:00:00 2001 From: Li Ming Date: Fri, 9 Aug 2024 08:27:50 +0000 Subject: [PATCH 2/2] cxl/test: Skip cxl_setup_parent_dport() for emulated dports The cxl_test unit test environment on qemu always hits below call trace with KASAN enabled: BUG: KASAN: slab-out-of-bounds in cxl_setup_parent_dport+0x480/0x530 [cxl_core] Read of size 1 at addr ff110000676014f8 by task (udev-worker)/676[ 24.424403] CPU: 2 PID: 676 Comm: (udev-worker) Tainted: G O N 6.10.0-qemucxl #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS edk2-20240214-2.el9 02/14/2024 Call Trace: dump_stack_lvl+0xea/0x150 print_report+0xce/0x610 ? kasan_complete_mode_report_info+0x40/0x200 kasan_report+0xcc/0x110 __asan_report_load1_noabort+0x18/0x20 cxl_setup_parent_dport+0x480/0x530 [cxl_core] cxl_mem_probe+0x49b/0xaa0 [cxl_mem] cxl_test module models a CXL topology for testing, it creates some emulated dports with platform devices in the CXL topology, so the dport_dev of an emulated dport points to a platform device rather than a pci device or a pci host bridge in the case. Currently, cxl_setup_parent_dport() is used to set up RAS and AER capability on the dport connected to the CXL memory device, but cxl_test does not support RAS or AER functionality yet, so the fix is implementing a __wrap_cxl_setup_parent_dport() to filter out all emulated dports, guarantees only real dports can be handled by cxl_setup_parent_dport(). Fixes: f05fd10d138d ("cxl/pci: Add RCH downstream port AER register discovery") Reported-by: Pengfei Xu Closes: https://lore.kernel.org/linux-cxl/ZrHTBp2O+HtUe6kt@xpf.sh.intel.com/T/#t Signed-off-by: Li Ming Reviewed-by: Dan Williams Reviewed-by: Ira Weiny Reviewed-by: Alison Schofield Tested-by: Ira Weiny Tested-by: Alison Schofield Link: https://patch.msgid.link/20240809082750.3015641-3-ming4.li@intel.com Signed-off-by: Dave Jiang --- tools/testing/cxl/Kbuild | 1 + tools/testing/cxl/test/mock.c | 12 ++++++++++++ 2 files changed, 13 insertions(+) diff --git a/tools/testing/cxl/Kbuild b/tools/testing/cxl/Kbuild index 030b388800f05..3d1ca9e38b1fa 100644 --- a/tools/testing/cxl/Kbuild +++ b/tools/testing/cxl/Kbuild @@ -14,6 +14,7 @@ ldflags-y += --wrap=cxl_dvsec_rr_decode ldflags-y += --wrap=devm_cxl_add_rch_dport ldflags-y += --wrap=cxl_rcd_component_reg_phys ldflags-y += --wrap=cxl_endpoint_parse_cdat +ldflags-y += --wrap=cxl_setup_parent_dport DRIVERS := ../../../drivers CXL_SRC := $(DRIVERS)/cxl diff --git a/tools/testing/cxl/test/mock.c b/tools/testing/cxl/test/mock.c index 6f737941dc0e1..d619672faa497 100644 --- a/tools/testing/cxl/test/mock.c +++ b/tools/testing/cxl/test/mock.c @@ -299,6 +299,18 @@ void __wrap_cxl_endpoint_parse_cdat(struct cxl_port *port) } EXPORT_SYMBOL_NS_GPL(__wrap_cxl_endpoint_parse_cdat, CXL); +void __wrap_cxl_setup_parent_dport(struct device *host, struct cxl_dport *dport) +{ + int index; + struct cxl_mock_ops *ops = get_cxl_mock_ops(&index); + + if (!ops || !ops->is_mock_port(dport->dport_dev)) + cxl_setup_parent_dport(host, dport); + + put_cxl_mock_ops(index); +} +EXPORT_SYMBOL_NS_GPL(__wrap_cxl_setup_parent_dport, CXL); + MODULE_LICENSE("GPL v2"); MODULE_IMPORT_NS(ACPI); MODULE_IMPORT_NS(CXL);