From 84ffae55af79d7b8834fd0c08d0d1ebf2c77f91e Mon Sep 17 00:00:00 2001 From: Anton Blanchard Date: Thu, 7 Apr 2011 21:44:21 +0000 Subject: [PATCH] powerpc: Fix oops if scan_dispatch_log is called too early We currently enable interrupts before the dispatch log for the boot cpu is setup. If a timer interrupt comes in early enough we oops in scan_dispatch_log: Unable to handle kernel paging request for data at address 0x00000010 ... .scan_dispatch_log+0xb0/0x170 .account_system_vtime+0xa0/0x220 .irq_enter+0x88/0xc0 .do_IRQ+0x48/0x230 The patch below adds a check to scan_dispatch_log to ensure the dispatch log has been allocated. Signed-off-by: Anton Blanchard Cc: Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/time.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index 375480c56eb9..f33acfd872ad 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -229,6 +229,9 @@ static u64 scan_dispatch_log(u64 stop_tb) u64 stolen = 0; u64 dtb; + if (!dtl) + return 0; + if (i == vpa->dtl_idx) return 0; while (i < vpa->dtl_idx) { -- 2.20.1