From mboxrd@z Thu Jan 1 00:00:00 1970 From: will.deacon@arm.com (Will Deacon) Date: Wed, 16 Apr 2014 09:15:06 +0100 Subject: [PATCH] arm64: initialize spinlock for init_mm's context In-Reply-To: <1397550050-5321-1-git-send-email-leoy@marvell.com> References: <1397550050-5321-1-git-send-email-leoy@marvell.com> Message-ID: <20140416081506.GB29754@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Apr 15, 2014 at 09:20:50AM +0100, Leo Yan wrote: > ARM64 has defined the spinlock for init_mm's context, so need initialize > the spinlock structure; otherwise during the suspend flow it will dump > the info for spinlock's bad magic warning as below: > > [ 39.084394] Disabling non-boot CPUs ... > [ 39.092871] BUG: spinlock bad magic on CPU#1, swapper/1/0 > [ 39.092896] lock: init_mm+0x338/0x3e0, .magic: 00000000, .owner: /-1, .owner_cpu: 0 > [ 39.092907] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G O 3.10.33 #125 > [ 39.092912] Call trace: > [ 39.092927] [] dump_backtrace+0x0/0x16c > [ 39.092934] [] show_stack+0x10/0x1c > [ 39.092947] [] dump_stack+0x1c/0x28 > [ 39.092953] [] spin_dump+0x78/0x88 > [ 39.092960] [] spin_bug+0x24/0x34 > [ 39.092971] [] do_raw_spin_lock+0x98/0x17c > [ 39.092979] [] _raw_spin_lock_irqsave+0x4c/0x60 > [ 39.092990] [] set_mm_context+0x1c/0x6c > [ 39.092996] [] __new_context+0x94/0x10c > [ 39.093007] [] idle_task_exit+0x104/0x1b0 > [ 39.093014] [] cpu_die+0x14/0x74 > [ 39.093021] [] arch_cpu_idle_dead+0x8/0x14 > [ 39.093030] [] cpu_startup_entry+0x1ec/0x258 > [ 39.093036] [] secondary_start_kernel+0x114/0x124 > > Signed-off-by: Leo Yan > --- > arch/arm64/include/asm/mmu.h | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/arm64/include/asm/mmu.h b/arch/arm64/include/asm/mmu.h > index f600d40..06a19bd 100644 > --- a/arch/arm64/include/asm/mmu.h > +++ b/arch/arm64/include/asm/mmu.h > @@ -22,6 +22,9 @@ typedef struct { > void *vdso; > } mm_context_t; > > +#define INIT_MM_CONTEXT(name) \ > + .context.id_lock = __RAW_SPIN_LOCK_INITIALIZER(name.context.id_lock), This should probably be __RAW_SPIN_LOCK_UNLOCKED instead. Other than that, the patch looks fine to me. I should really get around to porting the ASID allocator from arch/arm/, then we could kill this lock altogether. Will