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-rw-r--r--arch/x86/Kconfig2
-rw-r--r--arch/x86/entry/common.c2
-rw-r--r--arch/x86/entry/vdso/vclock_gettime.c2
-rw-r--r--arch/x86/events/core.c4
-rw-r--r--arch/x86/include/asm/mmu_context.h4
-rw-r--r--arch/x86/include/asm/qspinlock.h11
-rw-r--r--arch/x86/include/asm/refcount.h2
-rw-r--r--arch/x86/include/asm/rwsem.h84
-rw-r--r--arch/x86/include/asm/spinlock.h7
-rw-r--r--arch/x86/include/asm/vgtod.h2
-rw-r--r--arch/x86/kernel/espfix_64.c6
-rw-r--r--arch/x86/kernel/ldt.c2
-rw-r--r--arch/x86/kernel/nmi.c2
-rw-r--r--arch/x86/kernel/paravirt.c14
-rw-r--r--arch/x86/kernel/smpboot.c3
-rw-r--r--arch/x86/kvm/mmu.c4
-rw-r--r--arch/x86/kvm/page_track.c2
-rw-r--r--arch/x86/lib/rwsem.S12
-rw-r--r--arch/x86/mm/extable.c7
-rw-r--r--arch/x86/xen/p2m.c2
-rw-r--r--arch/x86/xen/spinlock.c6
21 files changed, 116 insertions, 64 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 2fdb23313dd5..9bceea6a5852 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -56,7 +56,7 @@ config X86
select ARCH_HAS_KCOV if X86_64
select ARCH_HAS_PMEM_API if X86_64
# Causing hangs/crashes, see the commit that added this change for details.
- select ARCH_HAS_REFCOUNT if BROKEN
+ select ARCH_HAS_REFCOUNT
select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
select ARCH_HAS_SET_MEMORY
select ARCH_HAS_SG_CHAIN
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index 03505ffbe1b6..eaa0ba66cf96 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -75,7 +75,7 @@ static long syscall_trace_enter(struct pt_regs *regs)
if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
BUG_ON(regs != task_pt_regs(current));
- work = ACCESS_ONCE(ti->flags) & _TIF_WORK_SYSCALL_ENTRY;
+ work = READ_ONCE(ti->flags) & _TIF_WORK_SYSCALL_ENTRY;
if (unlikely(work & _TIF_SYSCALL_EMU))
emulated = true;
diff --git a/arch/x86/entry/vdso/vclock_gettime.c b/arch/x86/entry/vdso/vclock_gettime.c
index fa8dbfcf7ed3..11b13c4b43d5 100644
--- a/arch/x86/entry/vdso/vclock_gettime.c
+++ b/arch/x86/entry/vdso/vclock_gettime.c
@@ -318,7 +318,7 @@ int gettimeofday(struct timeval *, struct timezone *)
notrace time_t __vdso_time(time_t *t)
{
/* This is atomic on x86 so we don't need any locks. */
- time_t result = ACCESS_ONCE(gtod->wall_time_sec);
+ time_t result = READ_ONCE(gtod->wall_time_sec);
if (t)
*t = result;
diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 80534d3c2480..140d33288e78 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -2118,7 +2118,7 @@ static int x86_pmu_event_init(struct perf_event *event)
event->destroy(event);
}
- if (ACCESS_ONCE(x86_pmu.attr_rdpmc))
+ if (READ_ONCE(x86_pmu.attr_rdpmc))
event->hw.flags |= PERF_X86_EVENT_RDPMC_ALLOWED;
return err;
@@ -2371,7 +2371,7 @@ static unsigned long get_segment_base(unsigned int segment)
struct ldt_struct *ldt;
/* IRQs are off, so this synchronizes with smp_store_release */
- ldt = lockless_dereference(current->active_mm->context.ldt);
+ ldt = READ_ONCE(current->active_mm->context.ldt);
if (!ldt || idx >= ldt->nr_entries)
return 0;
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index 6699fc441644..6d16d15d09a0 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -73,8 +73,8 @@ static inline void load_mm_ldt(struct mm_struct *mm)
#ifdef CONFIG_MODIFY_LDT_SYSCALL
struct ldt_struct *ldt;
- /* lockless_dereference synchronizes with smp_store_release */
- ldt = lockless_dereference(mm->context.ldt);
+ /* READ_ONCE synchronizes with smp_store_release */
+ ldt = READ_ONCE(mm->context.ldt);
/*
* Any change to mm->context.ldt is followed by an IPI to all
diff --git a/arch/x86/include/asm/qspinlock.h b/arch/x86/include/asm/qspinlock.h
index 9982dd96f093..5e16b5d40d32 100644
--- a/arch/x86/include/asm/qspinlock.h
+++ b/arch/x86/include/asm/qspinlock.h
@@ -2,6 +2,7 @@
#ifndef _ASM_X86_QSPINLOCK_H
#define _ASM_X86_QSPINLOCK_H
+#include <linux/jump_label.h>
#include <asm/cpufeature.h>
#include <asm-generic/qspinlock_types.h>
#include <asm/paravirt.h>
@@ -47,10 +48,14 @@ static inline void queued_spin_unlock(struct qspinlock *lock)
#endif
#ifdef CONFIG_PARAVIRT
+DECLARE_STATIC_KEY_TRUE(virt_spin_lock_key);
+
+void native_pv_lock_init(void) __init;
+
#define virt_spin_lock virt_spin_lock
static inline bool virt_spin_lock(struct qspinlock *lock)
{
- if (!static_cpu_has(X86_FEATURE_HYPERVISOR))
+ if (!static_branch_likely(&virt_spin_lock_key))
return false;
/*
@@ -66,6 +71,10 @@ static inline bool virt_spin_lock(struct qspinlock *lock)
return true;
}
+#else
+static inline void native_pv_lock_init(void)
+{
+}
#endif /* CONFIG_PARAVIRT */
#include <asm-generic/qspinlock.h>
diff --git a/arch/x86/include/asm/refcount.h b/arch/x86/include/asm/refcount.h
index ff871210b9f2..4e44250e7d0d 100644
--- a/arch/x86/include/asm/refcount.h
+++ b/arch/x86/include/asm/refcount.h
@@ -15,7 +15,7 @@
* back to the regular execution flow in .text.
*/
#define _REFCOUNT_EXCEPTION \
- ".pushsection .text.unlikely\n" \
+ ".pushsection .text..refcount\n" \
"111:\tlea %[counter], %%" _ASM_CX "\n" \
"112:\t" ASM_UD0 "\n" \
ASM_UNREACHABLE \
diff --git a/arch/x86/include/asm/rwsem.h b/arch/x86/include/asm/rwsem.h
index 4d38d85a16ad..4c25cf6caefa 100644
--- a/arch/x86/include/asm/rwsem.h
+++ b/arch/x86/include/asm/rwsem.h
@@ -61,18 +61,33 @@
/*
* lock for reading
*/
+#define ____down_read(sem, slow_path) \
+({ \
+ struct rw_semaphore* ret; \
+ asm volatile("# beginning down_read\n\t" \
+ LOCK_PREFIX _ASM_INC "(%[sem])\n\t" \
+ /* adds 0x00000001 */ \
+ " jns 1f\n" \
+ " call " slow_path "\n" \
+ "1:\n\t" \
+ "# ending down_read\n\t" \
+ : "+m" (sem->count), "=a" (ret), \
+ ASM_CALL_CONSTRAINT \
+ : [sem] "a" (sem) \
+ : "memory", "cc"); \
+ ret; \
+})
+
static inline void __down_read(struct rw_semaphore *sem)
{
- asm volatile("# beginning down_read\n\t"
- LOCK_PREFIX _ASM_INC "(%1)\n\t"
- /* adds 0x00000001 */
- " jns 1f\n"
- " call call_rwsem_down_read_failed\n"
- "1:\n\t"
- "# ending down_read\n\t"
- : "+m" (sem->count)
- : "a" (sem)
- : "memory", "cc");
+ ____down_read(sem, "call_rwsem_down_read_failed");
+}
+
+static inline int __down_read_killable(struct rw_semaphore *sem)
+{
+ if (IS_ERR(____down_read(sem, "call_rwsem_down_read_failed_killable")))
+ return -EINTR;
+ return 0;
}
/*
@@ -82,17 +97,18 @@ static inline bool __down_read_trylock(struct rw_semaphore *sem)
{
long result, tmp;
asm volatile("# beginning __down_read_trylock\n\t"
- " mov %0,%1\n\t"
+ " mov %[count],%[result]\n\t"
"1:\n\t"
- " mov %1,%2\n\t"
- " add %3,%2\n\t"
+ " mov %[result],%[tmp]\n\t"
+ " add %[inc],%[tmp]\n\t"
" jle 2f\n\t"
- LOCK_PREFIX " cmpxchg %2,%0\n\t"
+ LOCK_PREFIX " cmpxchg %[tmp],%[count]\n\t"
" jnz 1b\n\t"
"2:\n\t"
"# ending __down_read_trylock\n\t"
- : "+m" (sem->count), "=&a" (result), "=&r" (tmp)
- : "i" (RWSEM_ACTIVE_READ_BIAS)
+ : [count] "+m" (sem->count), [result] "=&a" (result),
+ [tmp] "=&r" (tmp)
+ : [inc] "i" (RWSEM_ACTIVE_READ_BIAS)
: "memory", "cc");
return result >= 0;
}
@@ -106,7 +122,7 @@ static inline bool __down_read_trylock(struct rw_semaphore *sem)
struct rw_semaphore* ret; \
\
asm volatile("# beginning down_write\n\t" \
- LOCK_PREFIX " xadd %1,(%4)\n\t" \
+ LOCK_PREFIX " xadd %[tmp],(%[sem])\n\t" \
/* adds 0xffff0001, returns the old value */ \
" test " __ASM_SEL(%w1,%k1) "," __ASM_SEL(%w1,%k1) "\n\t" \
/* was the active mask 0 before? */\
@@ -114,9 +130,9 @@ static inline bool __down_read_trylock(struct rw_semaphore *sem)
" call " slow_path "\n" \
"1:\n" \
"# ending down_write" \
- : "+m" (sem->count), "=d" (tmp), \
+ : "+m" (sem->count), [tmp] "=d" (tmp), \
"=a" (ret), ASM_CALL_CONSTRAINT \
- : "a" (sem), "1" (RWSEM_ACTIVE_WRITE_BIAS) \
+ : [sem] "a" (sem), "[tmp]" (RWSEM_ACTIVE_WRITE_BIAS) \
: "memory", "cc"); \
ret; \
})
@@ -142,21 +158,21 @@ static inline bool __down_write_trylock(struct rw_semaphore *sem)
bool result;
long tmp0, tmp1;
asm volatile("# beginning __down_write_trylock\n\t"
- " mov %0,%1\n\t"
+ " mov %[count],%[tmp0]\n\t"
"1:\n\t"
" test " __ASM_SEL(%w1,%k1) "," __ASM_SEL(%w1,%k1) "\n\t"
/* was the active mask 0 before? */
" jnz 2f\n\t"
- " mov %1,%2\n\t"
- " add %4,%2\n\t"
- LOCK_PREFIX " cmpxchg %2,%0\n\t"
+ " mov %[tmp0],%[tmp1]\n\t"
+ " add %[inc],%[tmp1]\n\t"
+ LOCK_PREFIX " cmpxchg %[tmp1],%[count]\n\t"
" jnz 1b\n\t"
"2:\n\t"
CC_SET(e)
"# ending __down_write_trylock\n\t"
- : "+m" (sem->count), "=&a" (tmp0), "=&r" (tmp1),
- CC_OUT(e) (result)
- : "er" (RWSEM_ACTIVE_WRITE_BIAS)
+ : [count] "+m" (sem->count), [tmp0] "=&a" (tmp0),
+ [tmp1] "=&r" (tmp1), CC_OUT(e) (result)
+ : [inc] "er" (RWSEM_ACTIVE_WRITE_BIAS)
: "memory");
return result;
}
@@ -168,14 +184,14 @@ static inline void __up_read(struct rw_semaphore *sem)
{
long tmp;
asm volatile("# beginning __up_read\n\t"
- LOCK_PREFIX " xadd %1,(%2)\n\t"
+ LOCK_PREFIX " xadd %[tmp],(%[sem])\n\t"
/* subtracts 1, returns the old value */
" jns 1f\n\t"
" call call_rwsem_wake\n" /* expects old value in %edx */
"1:\n"
"# ending __up_read\n"
- : "+m" (sem->count), "=d" (tmp)
- : "a" (sem), "1" (-RWSEM_ACTIVE_READ_BIAS)
+ : "+m" (sem->count), [tmp] "=d" (tmp)
+ : [sem] "a" (sem), "[tmp]" (-RWSEM_ACTIVE_READ_BIAS)
: "memory", "cc");
}
@@ -186,14 +202,14 @@ static inline void __up_write(struct rw_semaphore *sem)
{
long tmp;
asm volatile("# beginning __up_write\n\t"
- LOCK_PREFIX " xadd %1,(%2)\n\t"
+ LOCK_PREFIX " xadd %[tmp],(%[sem])\n\t"
/* subtracts 0xffff0001, returns the old value */
" jns 1f\n\t"
" call call_rwsem_wake\n" /* expects old value in %edx */
"1:\n\t"
"# ending __up_write\n"
- : "+m" (sem->count), "=d" (tmp)
- : "a" (sem), "1" (-RWSEM_ACTIVE_WRITE_BIAS)
+ : "+m" (sem->count), [tmp] "=d" (tmp)
+ : [sem] "a" (sem), "[tmp]" (-RWSEM_ACTIVE_WRITE_BIAS)
: "memory", "cc");
}
@@ -203,7 +219,7 @@ static inline void __up_write(struct rw_semaphore *sem)
static inline void __downgrade_write(struct rw_semaphore *sem)
{
asm volatile("# beginning __downgrade_write\n\t"
- LOCK_PREFIX _ASM_ADD "%2,(%1)\n\t"
+ LOCK_PREFIX _ASM_ADD "%[inc],(%[sem])\n\t"
/*
* transitions 0xZZZZ0001 -> 0xYYYY0001 (i386)
* 0xZZZZZZZZ00000001 -> 0xYYYYYYYY00000001 (x86_64)
@@ -213,7 +229,7 @@ static inline void __downgrade_write(struct rw_semaphore *sem)
"1:\n\t"
"# ending __downgrade_write\n"
: "+m" (sem->count)
- : "a" (sem), "er" (-RWSEM_WAITING_BIAS)
+ : [sem] "a" (sem), [inc] "er" (-RWSEM_WAITING_BIAS)
: "memory", "cc");
}
diff --git a/arch/x86/include/asm/spinlock.h b/arch/x86/include/asm/spinlock.h
index b34625796eb2..5b6bc7016c22 100644
--- a/arch/x86/include/asm/spinlock.h
+++ b/arch/x86/include/asm/spinlock.h
@@ -42,11 +42,4 @@
#include <asm/qrwlock.h>
-#define arch_read_lock_flags(lock, flags) arch_read_lock(lock)
-#define arch_write_lock_flags(lock, flags) arch_write_lock(lock)
-
-#define arch_spin_relax(lock) cpu_relax()
-#define arch_read_relax(lock) cpu_relax()
-#define arch_write_relax(lock) cpu_relax()
-
#endif /* _ASM_X86_SPINLOCK_H */
diff --git a/arch/x86/include/asm/vgtod.h b/arch/x86/include/asm/vgtod.h
index 52250681f68c..fb856c9f0449 100644
--- a/arch/x86/include/asm/vgtod.h
+++ b/arch/x86/include/asm/vgtod.h
@@ -49,7 +49,7 @@ static inline unsigned gtod_read_begin(const struct vsyscall_gtod_data *s)
unsigned ret;
repeat:
- ret = ACCESS_ONCE(s->seq);
+ ret = READ_ONCE(s->seq);
if (unlikely(ret & 1)) {
cpu_relax();
goto repeat;
diff --git a/arch/x86/kernel/espfix_64.c b/arch/x86/kernel/espfix_64.c
index 9c4e7ba6870c..7d7715dde901 100644
--- a/arch/x86/kernel/espfix_64.c
+++ b/arch/x86/kernel/espfix_64.c
@@ -155,14 +155,14 @@ void init_espfix_ap(int cpu)
page = cpu/ESPFIX_STACKS_PER_PAGE;
/* Did another CPU already set this up? */
- stack_page = ACCESS_ONCE(espfix_pages[page]);
+ stack_page = READ_ONCE(espfix_pages[page]);
if (likely(stack_page))
goto done;
mutex_lock(&espfix_init_mutex);
/* Did we race on the lock? */
- stack_page = ACCESS_ONCE(espfix_pages[page]);
+ stack_page = READ_ONCE(espfix_pages[page]);
if (stack_page)
goto unlock_done;
@@ -200,7 +200,7 @@ void init_espfix_ap(int cpu)
set_pte(&pte_p[n*PTE_STRIDE], pte);
/* Job is done for this CPU and any CPU which shares this page */
- ACCESS_ONCE(espfix_pages[page]) = stack_page;
+ WRITE_ONCE(espfix_pages[page], stack_page);
unlock_done:
mutex_unlock(&espfix_init_mutex);
diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c
index 4d17bacf4030..a2fcf037bd80 100644
--- a/arch/x86/kernel/ldt.c
+++ b/arch/x86/kernel/ldt.c
@@ -102,7 +102,7 @@ static void finalize_ldt_struct(struct ldt_struct *ldt)
static void install_ldt(struct mm_struct *current_mm,
struct ldt_struct *ldt)
{
- /* Synchronizes with lockless_dereference in load_mm_ldt. */
+ /* Synchronizes with READ_ONCE in load_mm_ldt. */
smp_store_release(&current_mm->context.ldt, ldt);
/* Activate the LDT for all CPUs using current_mm. */
diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c
index 35aafc95e4b8..18bc9b51ac9b 100644
--- a/arch/x86/kernel/nmi.c
+++ b/arch/x86/kernel/nmi.c
@@ -105,7 +105,7 @@ static void nmi_max_handler(struct irq_work *w)
{
struct nmiaction *a = container_of(w, struct nmiaction, irq_work);
int remainder_ns, decimal_msecs;
- u64 whole_msecs = ACCESS_ONCE(a->max_duration);
+ u64 whole_msecs = READ_ONCE(a->max_duration);
remainder_ns = do_div(whole_msecs, (1000 * 1000));
decimal_msecs = remainder_ns / 1000;
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 19a3e8f961c7..041096bdef86 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -115,8 +115,18 @@ unsigned paravirt_patch_jmp(void *insnbuf, const void *target,
return 5;
}
-/* Neat trick to map patch type back to the call within the
- * corresponding structure. */
+DEFINE_STATIC_KEY_TRUE(virt_spin_lock_key);
+
+void __init native_pv_lock_init(void)
+{
+ if (!static_cpu_has(X86_FEATURE_HYPERVISOR))
+ static_branch_disable(&virt_spin_lock_key);
+}
+
+/*
+ * Neat trick to map patch type back to the call within the
+ * corresponding structure.
+ */
static void *get_call_destination(u8 type)
{
struct paravirt_patch_template tmpl = {
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index ad59edd84de7..198416ddff01 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -77,6 +77,7 @@
#include <asm/i8259.h>
#include <asm/realmode.h>
#include <asm/misc.h>
+#include <asm/qspinlock.h>
/* Number of siblings per CPU package */
int smp_num_siblings = 1;
@@ -1357,6 +1358,8 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus)
pr_info("CPU0: ");
print_cpu_info(&cpu_data(0));
+ native_pv_lock_init();
+
uv_system_init();
set_mtrr_aps_delayed_init();
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 7a69cf053711..a119b361b8b7 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -443,7 +443,7 @@ static u64 __update_clear_spte_slow(u64 *sptep, u64 spte)
static u64 __get_spte_lockless(u64 *sptep)
{
- return ACCESS_ONCE(*sptep);
+ return READ_ONCE(*sptep);
}
#else
union split_spte {
@@ -4819,7 +4819,7 @@ static void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
* If we don't have indirect shadow pages, it means no page is
* write-protected, so we can exit simply.
*/
- if (!ACCESS_ONCE(vcpu->kvm->arch.indirect_shadow_pages))
+ if (!READ_ONCE(vcpu->kvm->arch.indirect_shadow_pages))
return;
remote_flush = local_flush = false;
diff --git a/arch/x86/kvm/page_track.c b/arch/x86/kvm/page_track.c
index ea67dc876316..01c1371f39f8 100644
--- a/arch/x86/kvm/page_track.c
+++ b/arch/x86/kvm/page_track.c
@@ -157,7 +157,7 @@ bool kvm_page_track_is_active(struct kvm_vcpu *vcpu, gfn_t gfn,
return false;
index = gfn_to_index(gfn, slot->base_gfn, PT_PAGE_TABLE_LEVEL);
- return !!ACCESS_ONCE(slot->arch.gfn_track[mode][index]);
+ return !!READ_ONCE(slot->arch.gfn_track[mode][index]);
}
void kvm_page_track_cleanup(struct kvm *kvm)
diff --git a/arch/x86/lib/rwsem.S b/arch/x86/lib/rwsem.S
index bf2c6074efd2..dc2ab6ea6768 100644
--- a/arch/x86/lib/rwsem.S
+++ b/arch/x86/lib/rwsem.S
@@ -98,6 +98,18 @@ ENTRY(call_rwsem_down_read_failed)
ret
ENDPROC(call_rwsem_down_read_failed)
+ENTRY(call_rwsem_down_read_failed_killable)
+ FRAME_BEGIN
+ save_common_regs
+ __ASM_SIZE(push,) %__ASM_REG(dx)
+ movq %rax,%rdi
+ call rwsem_down_read_failed_killable
+ __ASM_SIZE(pop,) %__ASM_REG(dx)
+ restore_common_regs
+ FRAME_END
+ ret
+ENDPROC(call_rwsem_down_read_failed_killable)
+
ENTRY(call_rwsem_down_write_failed)
FRAME_BEGIN
save_common_regs
diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c
index c3521e2be396..3321b446b66c 100644
--- a/arch/x86/mm/extable.c
+++ b/arch/x86/mm/extable.c
@@ -67,12 +67,17 @@ bool ex_handler_refcount(const struct exception_table_entry *fixup,
* wrapped around) will be set. Additionally, seeing the refcount
* reach 0 will set ZF (Zero Flag: result was zero). In each of
* these cases we want a report, since it's a boundary condition.
- *
+ * The SF case is not reported since it indicates post-boundary
+ * manipulations below zero or above INT_MAX. And if none of the
+ * flags are set, something has gone very wrong, so report it.
*/
if (regs->flags & (X86_EFLAGS_OF | X86_EFLAGS_ZF)) {
bool zero = regs->flags & X86_EFLAGS_ZF;
refcount_error_report(regs, zero ? "hit zero" : "overflow");
+ } else if ((regs->flags & X86_EFLAGS_SF) == 0) {
+ /* Report if none of OF, ZF, nor SF are set. */
+ refcount_error_report(regs, "unexpected saturation");
}
return true;
diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c
index 6083ba462f35..13b4f19b9131 100644
--- a/arch/x86/xen/p2m.c
+++ b/arch/x86/xen/p2m.c
@@ -547,7 +547,7 @@ int xen_alloc_p2m_entry(unsigned long pfn)
if (p2m_top_mfn && pfn < MAX_P2M_PFN) {
topidx = p2m_top_index(pfn);
top_mfn_p = &p2m_top_mfn[topidx];
- mid_mfn = ACCESS_ONCE(p2m_top_mfn_p[topidx]);
+ mid_mfn = READ_ONCE(p2m_top_mfn_p[topidx]);
BUG_ON(virt_to_mfn(mid_mfn) != *top_mfn_p);
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c
index 08324c64005d..02f3445a2b5f 100644
--- a/arch/x86/xen/spinlock.c
+++ b/arch/x86/xen/spinlock.c
@@ -11,6 +11,7 @@
#include <linux/slab.h>
#include <asm/paravirt.h>
+#include <asm/qspinlock.h>
#include <xen/interface/xen.h>
#include <xen/events.h>
@@ -81,8 +82,11 @@ void xen_init_lock_cpu(int cpu)
int irq;
char *name;
- if (!xen_pvspin)
+ if (!xen_pvspin) {
+ if (cpu == 0)
+ static_branch_disable(&virt_spin_lock_key);
return;
+ }
WARN(per_cpu(lock_kicker_irq, cpu) >= 0, "spinlock on CPU%d exists on IRQ%d!\n",
cpu, per_cpu(lock_kicker_irq, cpu));
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.