diff options
| author | Marc Zyngier <Marc.Zyngier@arm.com> | 2013-11-04 20:14:58 +0000 |
|---|---|---|
| committer | Ishan Mittal <imittal@nvidia.com> | 2014-04-30 15:03:37 +0530 |
| commit | f46f047918b1538de0415b0928dc6c980dd49581 (patch) | |
| tree | 2deca869f659a86ecd2a43e61028c4e6f41b108a | |
| parent | 1dbd0efc1da7429f372efecb8bbf1ddc9d71c743 (diff) | |
arm64: fix access to preempt_count from assembly code
preempt_count is defined as an int. Oddly enough, we access it
as a 64bit value. Things become interesting when running a BE
kernel, and looking at the current CPU number, which is stored
as an int next to preempt_count. Like in a per-cpu interrupt
handler, for example...
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Change-Id: I061cc6b76b282064535a919ec589cf9d80b73bed
Using a 32bit access fixes the issue for good.
(cherry picked from commit 717321fcb58ed95169bf344ae47ac6098ba5dfbe)
Cc: Matthew Leach <matthew.leach@arm.com>
Signed-off-by: Marc Zyngier <Marc.Zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| -rw-r--r-- | arch/arm64/kernel/entry.S | 22 |
1 files changed, 11 insertions, 11 deletions
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index d49886477e95..e91dedfff142 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -312,14 +312,14 @@ el1_irq: #endif #ifdef CONFIG_PREEMPT get_thread_info tsk - ldr x24, [tsk, #TI_PREEMPT] // get preempt count - add x0, x24, #1 // increment it - str x0, [tsk, #TI_PREEMPT] + ldr w24, [tsk, #TI_PREEMPT] // get preempt count + add w0, w24, #1 // increment it + str w0, [tsk, #TI_PREEMPT] #endif irq_handler #ifdef CONFIG_PREEMPT - str x24, [tsk, #TI_PREEMPT] // restore preempt count - cbnz x24, 1f // preempt count != 0 + str w24, [tsk, #TI_PREEMPT] // restore preempt count + cbnz w24, 1f // preempt count != 0 ldr x0, [tsk, #TI_FLAGS] // get flags tbz x0, #TIF_NEED_RESCHED, 1f // needs rescheduling? bl el1_preempt @@ -524,15 +524,15 @@ el0_irq_naked: #endif get_thread_info tsk #ifdef CONFIG_PREEMPT - ldr x24, [tsk, #TI_PREEMPT] // get preempt count - add x23, x24, #1 // increment it - str x23, [tsk, #TI_PREEMPT] + ldr w24, [tsk, #TI_PREEMPT] // get preempt count + add w23, w24, #1 // increment it + str w23, [tsk, #TI_PREEMPT] #endif irq_handler #ifdef CONFIG_PREEMPT - ldr x0, [tsk, #TI_PREEMPT] - str x24, [tsk, #TI_PREEMPT] - cmp x0, x23 + ldr w0, [tsk, #TI_PREEMPT] + str w24, [tsk, #TI_PREEMPT] + cmp w0, w23 b.eq 1f mov x1, #0 str x1, [x1] // BUG |