From 9372450cc22d185f708e5cc3557cf991be4b7dc5 Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Tue, 7 May 2013 19:28:52 +0000 Subject: parisc: add kernel stack overflow check Add the CONFIG_DEBUG_STACKOVERFLOW config option to enable checks to detect kernel stack overflows. Stack overflows can not be detected reliable since we do not want to introduce too much overhead. Instead, during irq processing in do_cpu_irq_mask() we check kernel stack usage of the interrupted kernel process. Kernel threads can be easily detected by checking the value of space register 7 (sr7) which is zero when running inside the kernel. Since THREAD_SIZE is 16k and PAGE_SIZE is 4k, reduce the alignment of the init thread to the lower value (PAGE_SIZE) in the kernel vmlinux.ld.S linker script. Signed-off-by: Helge Deller --- arch/parisc/include/asm/thread_info.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/parisc/include/asm/thread_info.h') diff --git a/arch/parisc/include/asm/thread_info.h b/arch/parisc/include/asm/thread_info.h index 6182832e5b6c..540c88fa8f86 100644 --- a/arch/parisc/include/asm/thread_info.h +++ b/arch/parisc/include/asm/thread_info.h @@ -40,7 +40,7 @@ struct thread_info { /* thread information allocation */ -#define THREAD_SIZE_ORDER 2 +#define THREAD_SIZE_ORDER 2 /* PA-RISC requires at least 16k stack */ /* Be sure to hunt all references to this down when you change the size of * the kernel stack */ #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER) -- cgit v1.2.3-59-g8ed1b