This is a note to let you know that I've just added the patch titled
perf/x86/intel: Fix unchecked MSR access error for Alder Lake N
to the 5.19-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-fix-unchecked-msr-access-error-for-al.patch
and it can be found in the queue-5.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 18f238fa2e428ab127ce1177799e96f9ddcd7930
Author: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Date: Wed Aug 31 07:27:02 2022 -0700
perf/x86/intel: Fix unchecked MSR access error for Alder Lake N
[ Upstream commit 24919fdea6f8b31d7cdf32ac291bc5dd0b023878 ]
For some Alder Lake N machine, the below unchecked MSR access error may be
triggered.
[ 0.088017] rcu: Hierarchical SRCU implementation.
[ 0.088017] unchecked MSR access error: WRMSR to 0x38f (tried to write
0x0001000f0000003f) at rIP: 0xffffffffb5684de8 (native_write_msr+0x8/0x30)
[ 0.088017] Call Trace:
[ 0.088017] <TASK>
[ 0.088017] __intel_pmu_enable_all.constprop.46+0x4a/0xa0
The Alder Lake N only has e-cores. The X86_FEATURE_HYBRID_CPU flag is
not set. The perf cannot retrieve the correct CPU type via
get_this_hybrid_cpu_type(). The model specific get_hybrid_cpu_type() is
hardcode to p-core. The wrong CPU type is given to the PMU of the
Alder Lake N.
Since Alder Lake N isn't in fact a hybrid CPU, remove ALDERLAKE_N from
the rest of {ALDER,RAPTOP}LAKE and create a non-hybrid PMU setup.
The differences between Gracemont and the previous Tremont are,
- Number of GP counters
- Load and store latency Events
- PEBS event_constraints
- Instruction Latency support
- Data source encoding
- Memory access latency encoding
Fixes: c2a960f7c574 ("perf/x86: Add new Alder Lake and Raptor Lake support")
Reported-by: Jianfeng Gao <jianfeng.gao@xxxxxxxxx>
Suggested-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20220831142702.153110-1-kan.liang@xxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index bd8b98857609..8d6befb24b8e 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -2101,6 +2101,15 @@ static struct extra_reg intel_tnt_extra_regs[] __read_mostly = {
EVENT_EXTRA_END
};
+EVENT_ATTR_STR(mem-loads, mem_ld_grt, "event=0xd0,umask=0x5,ldlat=3");
+EVENT_ATTR_STR(mem-stores, mem_st_grt, "event=0xd0,umask=0x6");
+
+static struct attribute *grt_mem_attrs[] = {
+ EVENT_PTR(mem_ld_grt),
+ EVENT_PTR(mem_st_grt),
+ NULL
+};
+
static struct extra_reg intel_grt_extra_regs[] __read_mostly = {
/* must define OFFCORE_RSP_X first, see intel_fixup_er() */
INTEL_UEVENT_EXTRA_REG(0x01b7, MSR_OFFCORE_RSP_0, 0x3fffffffffull, RSP_0),
@@ -5874,6 +5883,36 @@ __init int intel_pmu_init(void)
name = "Tremont";
break;
+ case INTEL_FAM6_ALDERLAKE_N:
+ x86_pmu.mid_ack = true;
+ memcpy(hw_cache_event_ids, glp_hw_cache_event_ids,
+ sizeof(hw_cache_event_ids));
+ memcpy(hw_cache_extra_regs, tnt_hw_cache_extra_regs,
+ sizeof(hw_cache_extra_regs));
+ hw_cache_event_ids[C(ITLB)][C(OP_READ)][C(RESULT_ACCESS)] = -1;
+
+ x86_pmu.event_constraints = intel_slm_event_constraints;
+ x86_pmu.pebs_constraints = intel_grt_pebs_event_constraints;
+ x86_pmu.extra_regs = intel_grt_extra_regs;
+
+ x86_pmu.pebs_aliases = NULL;
+ x86_pmu.pebs_prec_dist = true;
+ x86_pmu.pebs_block = true;
+ x86_pmu.lbr_pt_coexist = true;
+ x86_pmu.flags |= PMU_FL_HAS_RSP_1;
+ x86_pmu.flags |= PMU_FL_INSTR_LATENCY;
+
+ intel_pmu_pebs_data_source_grt();
+ x86_pmu.pebs_latency_data = adl_latency_data_small;
+ x86_pmu.get_event_constraints = tnt_get_event_constraints;
+ x86_pmu.limit_period = spr_limit_period;
+ td_attr = tnt_events_attrs;
+ mem_attr = grt_mem_attrs;
+ extra_attr = nhm_format_attr;
+ pr_cont("Gracemont events, ");
+ name = "gracemont";
+ break;
+
case INTEL_FAM6_WESTMERE:
case INTEL_FAM6_WESTMERE_EP:
case INTEL_FAM6_WESTMERE_EX:
@@ -6216,7 +6255,6 @@ __init int intel_pmu_init(void)
case INTEL_FAM6_ALDERLAKE:
case INTEL_FAM6_ALDERLAKE_L:
- case INTEL_FAM6_ALDERLAKE_N:
case INTEL_FAM6_RAPTORLAKE:
case INTEL_FAM6_RAPTORLAKE_P:
/*
diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c
index 9b48d957d2b3..139204aea94e 100644
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -110,13 +110,18 @@ void __init intel_pmu_pebs_data_source_skl(bool pmem)
__intel_pmu_pebs_data_source_skl(pmem, pebs_data_source);
}
-static void __init intel_pmu_pebs_data_source_grt(u64 *data_source)
+static void __init __intel_pmu_pebs_data_source_grt(u64 *data_source)
{
data_source[0x05] = OP_LH | P(LVL, L3) | LEVEL(L3) | P(SNOOP, HIT);
data_source[0x06] = OP_LH | P(LVL, L3) | LEVEL(L3) | P(SNOOP, HITM);
data_source[0x08] = OP_LH | P(LVL, L3) | LEVEL(L3) | P(SNOOPX, FWD);
}
+void __init intel_pmu_pebs_data_source_grt(void)
+{
+ __intel_pmu_pebs_data_source_grt(pebs_data_source);
+}
+
void __init intel_pmu_pebs_data_source_adl(void)
{
u64 *data_source;
@@ -127,7 +132,7 @@ void __init intel_pmu_pebs_data_source_adl(void)
data_source = x86_pmu.hybrid_pmu[X86_HYBRID_PMU_ATOM_IDX].pebs_data_source;
memcpy(data_source, pebs_data_source, sizeof(pebs_data_source));
- intel_pmu_pebs_data_source_grt(data_source);
+ __intel_pmu_pebs_data_source_grt(data_source);
}
static u64 precise_store_data(u64 status)
diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
index 821098aebf78..84f6f947ddef 100644
--- a/arch/x86/events/perf_event.h
+++ b/arch/x86/events/perf_event.h
@@ -1513,6 +1513,8 @@ void intel_pmu_pebs_data_source_skl(bool pmem);
void intel_pmu_pebs_data_source_adl(void);
+void intel_pmu_pebs_data_source_grt(void);
+
int intel_pmu_setup_lbr_filter(struct perf_event *event);
void intel_pt_interrupt(void);
