在 2018-03-22四的 22:21 +0000，James Hogan写道： > On Fri, Mar 16, 2018 at 03:55:16PM +0800, Huacai Chen wrote: > > diff --git a/arch/mips/boot/compressed/decompress.c > > b/arch/mips/boot/compressed/decompress.c > > index fdf99e9..5ba431c 100644 > > --- a/arch/mips/boot/compressed/decompress.c > > +++ b/arch/mips/boot/compressed/decompress.c > > @@ -78,11 +78,6 @@ void error(char *x) > > > > unsigned long __stack_chk_guard; > > ... > > > diff --git a/arch/mips/boot/compressed/head.S > > b/arch/mips/boot/compressed/head.S > > index 409cb48..00d0ee0 100644 > > --- a/arch/mips/boot/compressed/head.S > > +++ b/arch/mips/boot/compressed/head.S > > @@ -32,6 +32,10 @@ start: > > bne a2, a0, 1b > > addiu a0, a0, 4 > > > > + PTR_LA a0, __stack_chk_guard > > + PTR_LI a1, 0x000a0dff > > + sw a1, 0(a0) > Hi James Huacai Can't reply this mail. His chenhc@xxxxxxxxxx is blcoked by Linux-MIPS mailing list while his Gmail didn't receive this email, so I'm replying for him. > Should that not be LONG_S? Otherwise big endian MIPS64 would get a > word-swapped canary (which is probably mostly harmless, but still). Yes, he said it's considerable. > > Also I think it worth mentioning in the commit message the MIPS > configuration you hit this with, presumably a Loongson one? For me > decompress_kernel() gets a stack guard on loongson3_defconfig, but > not > malta_defconfig or malta_defconfig + 64-bit. I presume its sensitive > to > the compiler inlining stuff into decompress_kernel() or something > such > that it suddenly qualifies for a stack guard. Have you tested with CONFIG_CC_STACKPROTECTOR_STRONG=y ? Huacai reproduced the issue by this[1] config with GCC 4.9. [1] https://github.com/loongson-community/linux-stable/blob/rebase-4.14 /arch/mips/configs/loongson3_defconfig > > Cheers > James
