4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Matt Redfearn <[email protected]> commit 5fdc66e046206306bf61ff2d626bfa52ca087f7b upstream. Commit db8466c581cc ("MIPS: IRQ Stack: Unwind IRQ stack onto task stack") erroneously set the initial stack pointer of the IRQ stack to a value with a 4 byte alignment. The MIPS32 ABI requires that the minimum stack alignment is 8 byte, and the MIPS64 ABIs(n32/n64) require 16 byte minimum alignment. Fix IRQ_STACK_START such that it leaves space for the dummy stack frame (containing interrupted task kernel stack pointer) while also meeting minimum alignment requirements. Fixes: db8466c581cc ("MIPS: IRQ Stack: Unwind IRQ stack onto task stack") Reported-by: Darius Ivanauskas <[email protected]> Signed-off-by: Matt Redfearn <[email protected]> Cc: Chris Metcalf <[email protected]> Cc: Petr Mladek <[email protected]> Cc: Aaron Tomlin <[email protected]> Cc: Jason A. Donenfeld <[email protected]> Cc: [email protected] Cc: [email protected] Patchwork: https://patchwork.linux-mips.org/patch/16760/ Signed-off-by: Ralf Baechle <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/mips/include/asm/irq.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/mips/include/asm/irq.h +++ b/arch/mips/include/asm/irq.h @@ -18,7 +18,7 @@ #include <irq.h> #define IRQ_STACK_SIZE THREAD_SIZE -#define IRQ_STACK_START (IRQ_STACK_SIZE - sizeof(unsigned long)) +#define IRQ_STACK_START (IRQ_STACK_SIZE - 16) extern void *irq_stack[NR_CPUS];
