OMAP4 sleep entry code even though itself don't use many CPU registers makes call to the v7_flush_dcache_all() which uses them. Since v7_flush_dcache_all() doesn't make use of stack, the caller must take care of the stack frame. Otherwise it will lead to corrupted stack frame.
Fix it by saving used registers. Reported-by: Grygorii Strashko <[email protected]> Signed-off-by: Santosh Shilimkar <[email protected]> Cc: Kevin Hilman <[email protected]> --- v2: Added comment in the code. arch/arm/mach-omap2/sleep44xx.S | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/arm/mach-omap2/sleep44xx.S b/arch/arm/mach-omap2/sleep44xx.S index 9f6b83d..91e71d8 100644 --- a/arch/arm/mach-omap2/sleep44xx.S +++ b/arch/arm/mach-omap2/sleep44xx.S @@ -56,9 +56,13 @@ ppa_por_params: * The restore function pointer is stored at CPUx_WAKEUP_NS_PA_ADDR_OFFSET. * It returns to the caller for CPU INACTIVE and ON power states or in case * CPU failed to transition to targeted OFF/DORMANT state. + * + * omap4_finish_suspend() calls v7_flush_dcache_all() which doesn't save + * stack frame and it expects the caller to take care of it. Hence the entire + * stack frame is saved to avoid possible stack corruption. */ ENTRY(omap4_finish_suspend) - stmfd sp!, {lr} + stmfd sp!, {r4-r12, lr} cmp r0, #0x0 beq do_WFI @ No lowpower state, jump to WFI @@ -226,7 +230,7 @@ scu_gp_clear: skip_scu_gp_clear: isb dsb - ldmfd sp!, {pc} + ldmfd sp!, {r4-r12, pc} ENDPROC(omap4_finish_suspend) /* -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
