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authorLinus Torvalds <torvalds@linux-foundation.org>2023-01-15 07:17:44 -0600
committerLinus Torvalds <torvalds@linux-foundation.org>2023-01-15 07:17:44 -0600
commitf0f70ddb8f3bdbe670b1fab07271dd772e54c341 (patch)
tree3c2681c4860236c8296151f0651e23ade6b656c5
parent8aa9761223af6a075f9904d035b57cef9b26aaab (diff)
parent26ce6ec364f18d2915923bc05784084e54a5c4cc (diff)
Merge tag 'x86_urgent_for_v6.2_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov: - Make sure the poking PGD is pinned for Xen PV as it requires it this way - Fixes for two resctrl races when moving a task or creating a new monitoring group - Fix SEV-SNP guests running under HyperV where MTRRs are disabled to not return a UC- type mapping type on memremap() and thus cause a serious slowdown - Fix insn mnemonics in bioscall.S now that binutils is starting to fix confusing insn suffixes * tag 'x86_urgent_for_v6.2_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: fix poking_init() for Xen PV guests x86/resctrl: Fix event counts regression in reused RMIDs x86/resctrl: Fix task CLOSID/RMID update race x86/pat: Fix pat_x_mtrr_type() for MTRR disabled case x86/boot: Avoid using Intel mnemonics in AT&T syntax asm
-rw-r--r--arch/x86/boot/bioscall.S4
-rw-r--r--arch/x86/kernel/cpu/resctrl/monitor.c49
-rw-r--r--arch/x86/kernel/cpu/resctrl/rdtgroup.c12
-rw-r--r--arch/x86/mm/init.c4
-rw-r--r--arch/x86/mm/pat/memtype.c3
5 files changed, 52 insertions, 20 deletions
diff --git a/arch/x86/boot/bioscall.S b/arch/x86/boot/bioscall.S
index 5521ea12f44e..aa9b96457584 100644
--- a/arch/x86/boot/bioscall.S
+++ b/arch/x86/boot/bioscall.S
@@ -32,7 +32,7 @@ intcall:
movw %dx, %si
movw %sp, %di
movw $11, %cx
- rep; movsd
+ rep; movsl
/* Pop full state from the stack */
popal
@@ -67,7 +67,7 @@ intcall:
jz 4f
movw %sp, %si
movw $11, %cx
- rep; movsd
+ rep; movsl
4: addw $44, %sp
/* Restore state and return */
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index efe0c30d3a12..77538abeb72a 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -146,6 +146,30 @@ static inline struct rmid_entry *__rmid_entry(u32 rmid)
return entry;
}
+static int __rmid_read(u32 rmid, enum resctrl_event_id eventid, u64 *val)
+{
+ u64 msr_val;
+
+ /*
+ * As per the SDM, when IA32_QM_EVTSEL.EvtID (bits 7:0) is configured
+ * with a valid event code for supported resource type and the bits
+ * IA32_QM_EVTSEL.RMID (bits 41:32) are configured with valid RMID,
+ * IA32_QM_CTR.data (bits 61:0) reports the monitored data.
+ * IA32_QM_CTR.Error (bit 63) and IA32_QM_CTR.Unavailable (bit 62)
+ * are error bits.
+ */
+ wrmsr(MSR_IA32_QM_EVTSEL, eventid, rmid);
+ rdmsrl(MSR_IA32_QM_CTR, msr_val);
+
+ if (msr_val & RMID_VAL_ERROR)
+ return -EIO;
+ if (msr_val & RMID_VAL_UNAVAIL)
+ return -EINVAL;
+
+ *val = msr_val;
+ return 0;
+}
+
static struct arch_mbm_state *get_arch_mbm_state(struct rdt_hw_domain *hw_dom,
u32 rmid,
enum resctrl_event_id eventid)
@@ -172,8 +196,12 @@ void resctrl_arch_reset_rmid(struct rdt_resource *r, struct rdt_domain *d,
struct arch_mbm_state *am;
am = get_arch_mbm_state(hw_dom, rmid, eventid);
- if (am)
+ if (am) {
memset(am, 0, sizeof(*am));
+
+ /* Record any initial, non-zero count value. */
+ __rmid_read(rmid, eventid, &am->prev_msr);
+ }
}
static u64 mbm_overflow_count(u64 prev_msr, u64 cur_msr, unsigned int width)
@@ -191,25 +219,14 @@ int resctrl_arch_rmid_read(struct rdt_resource *r, struct rdt_domain *d,
struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);
struct arch_mbm_state *am;
u64 msr_val, chunks;
+ int ret;
if (!cpumask_test_cpu(smp_processor_id(), &d->cpu_mask))
return -EINVAL;
- /*
- * As per the SDM, when IA32_QM_EVTSEL.EvtID (bits 7:0) is configured
- * with a valid event code for supported resource type and the bits
- * IA32_QM_EVTSEL.RMID (bits 41:32) are configured with valid RMID,
- * IA32_QM_CTR.data (bits 61:0) reports the monitored data.
- * IA32_QM_CTR.Error (bit 63) and IA32_QM_CTR.Unavailable (bit 62)
- * are error bits.
- */
- wrmsr(MSR_IA32_QM_EVTSEL, eventid, rmid);
- rdmsrl(MSR_IA32_QM_CTR, msr_val);
-
- if (msr_val & RMID_VAL_ERROR)
- return -EIO;
- if (msr_val & RMID_VAL_UNAVAIL)
- return -EINVAL;
+ ret = __rmid_read(rmid, eventid, &msr_val);
+ if (ret)
+ return ret;
am = get_arch_mbm_state(hw_dom, rmid, eventid);
if (am) {
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index e5a48f05e787..5993da21d822 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -580,8 +580,10 @@ static int __rdtgroup_move_task(struct task_struct *tsk,
/*
* Ensure the task's closid and rmid are written before determining if
* the task is current that will decide if it will be interrupted.
+ * This pairs with the full barrier between the rq->curr update and
+ * resctrl_sched_in() during context switch.
*/
- barrier();
+ smp_mb();
/*
* By now, the task's closid and rmid are set. If the task is current
@@ -2402,6 +2404,14 @@ static void rdt_move_group_tasks(struct rdtgroup *from, struct rdtgroup *to,
WRITE_ONCE(t->rmid, to->mon.rmid);
/*
+ * Order the closid/rmid stores above before the loads
+ * in task_curr(). This pairs with the full barrier
+ * between the rq->curr update and resctrl_sched_in()
+ * during context switch.
+ */
+ smp_mb();
+
+ /*
* If the task is on a CPU, set the CPU in the mask.
* The detection is inaccurate as tasks might move or
* schedule before the smp function call takes place.
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index d3987359d441..cb258f58fdc8 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -26,6 +26,7 @@
#include <asm/pti.h>
#include <asm/text-patching.h>
#include <asm/memtype.h>
+#include <asm/paravirt.h>
/*
* We need to define the tracepoints somewhere, and tlb.c
@@ -804,6 +805,9 @@ void __init poking_init(void)
poking_mm = mm_alloc();
BUG_ON(!poking_mm);
+ /* Xen PV guests need the PGD to be pinned. */
+ paravirt_arch_dup_mmap(NULL, poking_mm);
+
/*
* Randomize the poking address, but make sure that the following page
* will be mapped at the same PMD. We need 2 pages, so find space for 3,
diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c
index 46de9cf5c91d..fb4b1b5e0dea 100644
--- a/arch/x86/mm/pat/memtype.c
+++ b/arch/x86/mm/pat/memtype.c
@@ -387,7 +387,8 @@ static unsigned long pat_x_mtrr_type(u64 start, u64 end,
u8 mtrr_type, uniform;
mtrr_type = mtrr_type_lookup(start, end, &uniform);
- if (mtrr_type != MTRR_TYPE_WRBACK)
+ if (mtrr_type != MTRR_TYPE_WRBACK &&
+ mtrr_type != MTRR_TYPE_INVALID)
return _PAGE_CACHE_MODE_UC_MINUS;
return _PAGE_CACHE_MODE_WB;