Some kernels report a few unaligned exceptions during early userspace: init(1): unaligned access to 0x6000000000089f0b, ip=0x40000000000e3581 init(1): unaligned access to 0x6000000000089f13, ip=0x40000000000e3620 init(1): unaligned access to 0x6000000000089f11, ip=0x40000000000e3640 init(1): unaligned access to 0x600000000008af1b, ip=0x40000000000e3581 init(1): unaligned access to 0x600000000008af23, ip=0x40000000000e3620 fsck(3193): unaligned access to 0x600000000001255b, ip=0x2000000000069491 fsck(3193): unaligned access to 0x6000000000012563, ip=0x2000000000069530 fsck(3193): unaligned access to 0x6000000000012561, ip=0x2000000000069550 mount(3205): unaligned access to 0x6000000000012c2b, ip=0x2000000000069491 mount(3205): unaligned access to 0x6000000000012c33, ip=0x2000000000069530 mount(3855): unaligned access to 0x6000000000012c6b, ip=0x2000000000069491 mount(3855): unaligned access to 0x6000000000012c73, ip=0x2000000000069530 mount(3855): unaligned access to 0x6000000000012c71, ip=0x2000000000069550 while others do not report these exceptions. A git bisection pointed at an apparently innocent commit. The real problem is that we do not explicitly set or clear PSR.ac (we do clear it when executing 32-bit x86 binaries) so it is randomly set or clear in different kernel builds. Fix is to clear PSR.ac before transitioning to user code. Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx> --- Does the use of "rum" instruction need some paravirtualization? It is not in a critical path (used a couple of times during boot). diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S index 7ef0c59..595a0b6 100644 --- a/arch/ia64/kernel/entry.S +++ b/arch/ia64/kernel/entry.S @@ -499,6 +499,7 @@ GLOBAL_ENTRY(prefetch_stack) END(prefetch_stack) GLOBAL_ENTRY(kernel_execve) + rum IA64_PSR_AC mov r15=__NR_execve // put syscall number in place break __BREAK_SYSCALL br.ret.sptk.many rp -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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