Messages in this thread | | | Date | Tue, 21 Nov 2017 08:20:37 +0100 | From | Ingo Molnar <> | Subject | Re: [PATCH 11/16] x86/asm/64: Use a percpu trampoline stack for IDT entries |
| |
* Andy Lutomirski <luto@kernel.org> wrote:
> diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c > index 1ea03027a4a9..e4a941be96cf 100644 > --- a/arch/x86/kernel/traps.c > +++ b/arch/x86/kernel/traps.c
> -asmlinkage __visible notrace > +asmlinkage __visible notrace __no_sanitize_address > struct bad_iret_stack *fixup_bad_iret(struct bad_iret_stack *s) > { > /* > * This is called from entry_64.S early in handling a fault > * caused by a bad iret to user mode. To handle the fault > - * correctly, we want move our stack frame to task_pt_regs > - * and we want to pretend that the exception came from the > - * iret target. > + * correctly, we want move our stack frame to where it would > + * be had we entered directly on the entry stack (rather than > + * just below the IRET frame) and we want to pretend that the > + * exception came from the iret target. > */ > struct bad_iret_stack *new_stack = > - container_of(task_pt_regs(current), > - struct bad_iret_stack, regs); > + (struct bad_iret_stack *)this_cpu_read(cpu_tss.x86_tss.sp0) - 1; > > /* Copy the IRET target to the new stack. */ > memmove(&new_stack->regs.ip, (void *)s->regs.sp, 5*8);
So the addition of the __no_sanitize_address attribute to fixup_bad_iret() made the 64-bit allyesconfig/allmodconfig kernels fail the build:
In file included from ./include/linux/bitmap.h:9:0, arch/x86/kernel/traps.c: In function ‘fixup_bad_iret’: ./include/linux/string.h:344:24: error: inlining failed in call to always_inline ‘memmove’: function attribute mismatch __FORTIFY_INLINE void *memmove(void *p, const void *q, __kernel_size_t size) arch/x86/kernel/traps.c:645:2: error: called from here In file included from ./include/linux/bitmap.h:9:0, ./include/linux/string.h:344:24: error: inlining failed in call to always_inline ‘memmove’: function attribute mismatch __FORTIFY_INLINE void *memmove(void *p, const void *q, __kernel_size_t size) arch/x86/kernel/traps.c:642:2: error: called from here scripts/Makefile.build:314: recipe for target 'arch/x86/kernel/traps.o' failed
Thanks,
Ingo
| |