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authorStefan Agner <stefan.agner@toradex.com>2019-06-03 10:59:09 +0200
committerStefan Agner <stefan.agner@toradex.com>2019-06-03 10:59:09 +0200
commit2115c1bc6e396d5ffe9ecbe394d1c50a6e25c404 (patch)
tree20fff445991414f23c0a29237940b75cd756de86 /arch/arm64/include
parentb794ea49ba3816c0d5cf05506964a8e69ce4efa3 (diff)
parent3f7c1cab1a61108821cf47dda8a32ed25cc3588b (diff)
Merge tag 'v5.0.19' into toradex_5.0.ytoradex_5.0.y
This is the 5.0.19 stable release
Diffstat (limited to 'arch/arm64/include')
-rw-r--r--arch/arm64/include/asm/arch_timer.h33
-rw-r--r--arch/arm64/include/asm/processor.h8
2 files changed, 39 insertions, 2 deletions
diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h
index f2a234d6516c..93e07512b4b6 100644
--- a/arch/arm64/include/asm/arch_timer.h
+++ b/arch/arm64/include/asm/arch_timer.h
@@ -148,18 +148,47 @@ static inline void arch_timer_set_cntkctl(u32 cntkctl)
isb();
}
+/*
+ * Ensure that reads of the counter are treated the same as memory reads
+ * for the purposes of ordering by subsequent memory barriers.
+ *
+ * This insanity brought to you by speculative system register reads,
+ * out-of-order memory accesses, sequence locks and Thomas Gleixner.
+ *
+ * http://lists.infradead.org/pipermail/linux-arm-kernel/2019-February/631195.html
+ */
+#define arch_counter_enforce_ordering(val) do { \
+ u64 tmp, _val = (val); \
+ \
+ asm volatile( \
+ " eor %0, %1, %1\n" \
+ " add %0, sp, %0\n" \
+ " ldr xzr, [%0]" \
+ : "=r" (tmp) : "r" (_val)); \
+} while (0)
+
static inline u64 arch_counter_get_cntpct(void)
{
+ u64 cnt;
+
isb();
- return arch_timer_reg_read_stable(cntpct_el0);
+ cnt = arch_timer_reg_read_stable(cntpct_el0);
+ arch_counter_enforce_ordering(cnt);
+ return cnt;
}
static inline u64 arch_counter_get_cntvct(void)
{
+ u64 cnt;
+
isb();
- return arch_timer_reg_read_stable(cntvct_el0);
+ cnt = arch_timer_reg_read_stable(cntvct_el0);
+ arch_counter_enforce_ordering(cnt);
+ return cnt;
}
+#undef arch_counter_enforce_ordering
+
static inline int arch_timer_arch_init(void)
{
return 0;
diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h
index f1a7ab18faf3..928f59340598 100644
--- a/arch/arm64/include/asm/processor.h
+++ b/arch/arm64/include/asm/processor.h
@@ -57,7 +57,15 @@
#define TASK_SIZE_64 (UL(1) << vabits_user)
#ifdef CONFIG_COMPAT
+#ifdef CONFIG_ARM64_64K_PAGES
+/*
+ * With CONFIG_ARM64_64K_PAGES enabled, the last page is occupied
+ * by the compat vectors page.
+ */
#define TASK_SIZE_32 UL(0x100000000)
+#else
+#define TASK_SIZE_32 (UL(0x100000000) - PAGE_SIZE)
+#endif /* CONFIG_ARM64_64K_PAGES */
#define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \
TASK_SIZE_32 : TASK_SIZE_64)
#define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \