From: Josip Rodin <joy@xxxxxxxxxxxxxx> Date: Sun, 22 Nov 2009 23:06:21 +0100 >> [ 82.663939] Kernel unaligned access at TPC[46d24c] >> notifier_chain_register+0x10/0x38 >> [ 82.671606] Unable to handle kernel paging request in mna handler<1> >> at virtual address e00000a00b000046 That address is not only unaligned, it's completely out of range for valid kernel virtual addresses. notifier_chain_register() and their ilk are pretty simply and take constant kernel symbol addresses rather than, for example, dynamically allocated memory or something else more easily corrupted. So this is even more mysterious. Backtrace is: >> [ 82.759812] RPC: <atomic_notifier_chain_register+0x1c/0x44> ... >> [ 82.800022] I7: <kernel_init+0x38/0x204> ... >> [ 82.803917] Caller[0000000000782128]: kernel_init+0x38/0x204 >> [ 82.809549] Caller[0000000000426df8]: kernel_thread+0x38/0x48 >> [ 82.815268] Caller[000000000067bae0]: rest_init+0x18/0x60 And I can't see anything that registers notifiers from kernel_init(). I suspect the real caller of atomic_notifier_chain_register() is being optimized out by tail-call optimizations so we can't see exactly what it is. Can you build a test kernel with something like the following patch applied and reproduce? Thanks. diff --git a/Makefile b/Makefile index aa3e13a..d953cd3 100644 --- a/Makefile +++ b/Makefile @@ -537,6 +537,8 @@ ifndef CONFIG_CC_STACKPROTECTOR KBUILD_CFLAGS += $(call cc-option, -fno-stack-protector) endif +KBUILD_CFLAGS += -fno-optimize-sibling-calls + ifdef CONFIG_FRAME_POINTER KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls else -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
