4.4-stable review patch. If anyone has any objections, please let me know.
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From: Kan Liang kan.liang@linux.intel.com
commit 9e63a7894fd302082cf3627fe90844421a6cbe7f upstream.
Some PCI uncore PMUs cannot be registered on an 8-socket system (HPE Superdome Flex).
To understand which Socket the PCI uncore PMUs belongs to, perf retrieves the local Node ID of the uncore device from CPUNODEID(0xC0) of the PCI configuration space, and the mapping between Socket ID and Node ID from GIDNIDMAP(0xD4). The Socket ID can be calculated accordingly.
The local Node ID is only available at bit 2:0, but current code doesn't mask it. If a BIOS doesn't clear the rest of the bits, an incorrect Node ID will be fetched.
Filter the Node ID by adding a mask.
Reported-by: Song Liu songliubraving@fb.com Tested-by: Song Liu songliubraving@fb.com Signed-off-by: Kan Liang kan.liang@linux.intel.com Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Arnaldo Carvalho de Melo acme@redhat.com Cc: Jiri Olsa jolsa@redhat.com Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Cc: stable@vger.kernel.org # v3.7+ Fixes: 7c94ee2e0917 ("perf/x86: Add Intel Nehalem and Sandy Bridge-EP uncore support") Link: https://lkml.kernel.org/r/1548600794-33162-1-git-send-email-kan.liang@linux.... Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/kernel/cpu/perf_event_intel_uncore_snbep.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/arch/x86/kernel/cpu/perf_event_intel_uncore_snbep.c +++ b/arch/x86/kernel/cpu/perf_event_intel_uncore_snbep.c @@ -1081,6 +1081,8 @@ static struct pci_driver snbep_uncore_pc .id_table = snbep_uncore_pci_ids, };
+#define NODE_ID_MASK 0x7 + /* * build pci bus to socket mapping */ @@ -1102,7 +1104,7 @@ static int snbep_pci2phy_map_init(int de err = pci_read_config_dword(ubox_dev, 0x40, &config); if (err) break; - nodeid = config; + nodeid = config & NODE_ID_MASK; /* get the Node ID mapping */ err = pci_read_config_dword(ubox_dev, 0x54, &config); if (err)