diff options
| author | Andy Lutomirski <luto@kernel.org> | 2020-07-03 10:02:55 -0700 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2020-07-04 19:47:25 +0200 |
| commit | f41f0824224eb12ad84de8972962dd54be5abe3b (patch) | |
| tree | 6cf0f72f726f716884553c14fbc6318318de5776 /arch/x86/include | |
| parent | 3c73b81a9164d0c1b6379d6672d2772a9e95168e (diff) | |
x86/entry/xen: Route #DB correctly on Xen PV
On Xen PV, #DB doesn't use IST. It still needs to be correctly routed
depending on whether it came from user or kernel mode.
Get rid of DECLARE/DEFINE_IDTENTRY_XEN -- it was too hard to follow the
logic. Instead, route #DB and NMI through DECLARE/DEFINE_IDTENTRY_RAW on
Xen, and do the right thing for #DB. Also add more warnings to the
exc_debug* handlers to make this type of failure more obvious.
This fixes various forms of corruption that happen when usermode
triggers #DB on Xen PV.
Fixes: 4c0dcd8350a0 ("x86/entry: Implement user mode C entry points for #DB and #MCE")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/4163e733cce0b41658e252c6c6b3464f33fdff17.1593795633.git.luto@kernel.org
Diffstat (limited to 'arch/x86/include')
| -rw-r--r-- | arch/x86/include/asm/idtentry.h | 24 |
1 files changed, 6 insertions, 18 deletions
diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index cf51c50eb356..94333ac3092b 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -398,18 +398,6 @@ __visible noinstr void func(struct pt_regs *regs, \ #define DEFINE_IDTENTRY_DEBUG DEFINE_IDTENTRY_IST #define DEFINE_IDTENTRY_DEBUG_USER DEFINE_IDTENTRY_NOIST -/** - * DECLARE_IDTENTRY_XEN - Declare functions for XEN redirect IDT entry points - * @vector: Vector number (ignored for C) - * @func: Function name of the entry point - * - * Used for xennmi and xendebug redirections. No DEFINE as this is all ASM - * indirection magic. - */ -#define DECLARE_IDTENTRY_XEN(vector, func) \ - asmlinkage void xen_asm_exc_xen##func(void); \ - asmlinkage void asm_exc_xen##func(void) - #else /* !__ASSEMBLY__ */ /* @@ -469,10 +457,6 @@ __visible noinstr void func(struct pt_regs *regs, \ /* No ASM code emitted for NMI */ #define DECLARE_IDTENTRY_NMI(vector, func) -/* XEN NMI and DB wrapper */ -#define DECLARE_IDTENTRY_XEN(vector, func) \ - idtentry vector asm_exc_xen##func exc_##func has_error_code=0 - /* * ASM code to emit the common vector entry stubs where each stub is * packed into 8 bytes. @@ -570,11 +554,15 @@ DECLARE_IDTENTRY_MCE(X86_TRAP_MC, exc_machine_check); /* NMI */ DECLARE_IDTENTRY_NMI(X86_TRAP_NMI, exc_nmi); -DECLARE_IDTENTRY_XEN(X86_TRAP_NMI, nmi); +#ifdef CONFIG_XEN_PV +DECLARE_IDTENTRY_RAW(X86_TRAP_NMI, xenpv_exc_nmi); +#endif /* #DB */ DECLARE_IDTENTRY_DEBUG(X86_TRAP_DB, exc_debug); -DECLARE_IDTENTRY_XEN(X86_TRAP_DB, debug); +#ifdef CONFIG_XEN_PV +DECLARE_IDTENTRY_RAW(X86_TRAP_DB, xenpv_exc_debug); +#endif /* #DF */ DECLARE_IDTENTRY_DF(X86_TRAP_DF, exc_double_fault); |