This is a note to let you know that I've just added the patch titled perf/x86/intel/uncore: Support extra IMC channel on Ice Lake server to the 5.15-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: perf-x86-intel-uncore-support-extra-imc-channel-on-ice-lake-server.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 496a18f09374ad89b3ab4366019bc3975db90234 Mon Sep 17 00:00:00 2001 From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx> Date: Thu, 26 Aug 2021 08:32:37 -0700 Subject: perf/x86/intel/uncore: Support extra IMC channel on Ice Lake server From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx> commit 496a18f09374ad89b3ab4366019bc3975db90234 upstream. There are three channels on a Ice Lake server, but only two channels will ever be active. Current perf only enables two channels. Support the extra IMC channel, which may be activated on some Ice Lake machines. For a non-activated channel, the SW can still access it. The write will be ignored by the HW. 0 is always returned for the reading. Fixes: 2b3b76b5ec67 ("perf/x86/intel/uncore: Add Ice Lake server uncore support") Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Reviewed-by: Andi Kleen <ak@xxxxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Link: https://lkml.kernel.org/r/1629991963-102621-2-git-send-email-kan.liang@xxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/events/intel/uncore_snbep.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/arch/x86/events/intel/uncore_snbep.c +++ b/arch/x86/events/intel/uncore_snbep.c @@ -452,7 +452,7 @@ #define ICX_M3UPI_PCI_PMON_BOX_CTL 0xa0 /* ICX IMC */ -#define ICX_NUMBER_IMC_CHN 2 +#define ICX_NUMBER_IMC_CHN 3 #define ICX_IMC_MEM_STRIDE 0x4 /* SPR */ @@ -5463,7 +5463,7 @@ static struct intel_uncore_ops icx_uncor static struct intel_uncore_type icx_uncore_imc = { .name = "imc", .num_counters = 4, - .num_boxes = 8, + .num_boxes = 12, .perf_ctr_bits = 48, .fixed_ctr_bits = 48, .fixed_ctr = SNR_IMC_MMIO_PMON_FIXED_CTR, Patches currently in stable-queue which might be from kan.liang@xxxxxxxxxxxxxxx are queue-5.15/perf-x86-intel-uncore-fix-invalid-unit-check.patch queue-5.15/perf-x86-intel-uncore-fix-intel-icx-iio-event-constraints.patch queue-5.15/perf-x86-intel-uncore-support-extra-imc-channel-on-ice-lake-server.patch