From f08e32ec3cfcf9e6d3640007de590c225ab2e201 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 25 Feb 2020 23:33:28 +0100 Subject: [PATCH] x86/idtentry: Provide IDTRENTRY_NOIST variants for #DB and #MC Provide NOIST entry point macros which allows to implement NOIST variants of the C entry points. These are invoked when #DB or #MC enter from user space. This allows explicit handling of the difference between user mode and kernel mode entry later. Signed-off-by: Thomas Gleixner Reviewed-by: Alexandre Chartre Acked-by: Peter Zijlstra Acked-by: Andy Lutomirski Link: https://lkml.kernel.org/r/20200505135315.084882104@linutronix.de --- arch/x86/include/asm/idtentry.h | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index fcd4230a..060f9e3 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -138,10 +138,12 @@ __visible noinstr void func(struct pt_regs *regs) * @vector: Vector number (ignored for C) * @func: Function name of the entry point * - * Maps to DECLARE_IDTENTRY_RAW + * Maps to DECLARE_IDTENTRY_RAW, but declares also the NOIST C handler + * which is called from the ASM entry point on user mode entry */ #define DECLARE_IDTENTRY_IST(vector, func) \ - DECLARE_IDTENTRY_RAW(vector, func) + DECLARE_IDTENTRY_RAW(vector, func); \ + __visible void noist_##func(struct pt_regs *regs) /** * DEFINE_IDTENTRY_IST - Emit code for IST entry points @@ -152,6 +154,17 @@ __visible noinstr void func(struct pt_regs *regs) #define DEFINE_IDTENTRY_IST(func) \ DEFINE_IDTENTRY_RAW(func) +/** + * DEFINE_IDTENTRY_NOIST - Emit code for NOIST entry points which + * belong to a IST entry point (MCE, DB) + * @func: Function name of the entry point. Must be the same as + * the function name of the corresponding IST variant + * + * Maps to DEFINE_IDTENTRY_RAW(). + */ +#define DEFINE_IDTENTRY_NOIST(func) \ + DEFINE_IDTENTRY_RAW(noist_##func) + #else /* CONFIG_X86_64 */ /* Maps to a regular IDTENTRY on 32bit for now */ # define DECLARE_IDTENTRY_IST DECLARE_IDTENTRY @@ -161,12 +174,14 @@ __visible noinstr void func(struct pt_regs *regs) /* C-Code mapping */ #define DECLARE_IDTENTRY_MCE DECLARE_IDTENTRY_IST #define DEFINE_IDTENTRY_MCE DEFINE_IDTENTRY_IST +#define DEFINE_IDTENTRY_MCE_USER DEFINE_IDTENTRY_NOIST #define DECLARE_IDTENTRY_NMI DECLARE_IDTENTRY_IST #define DEFINE_IDTENTRY_NMI DEFINE_IDTENTRY_IST #define DECLARE_IDTENTRY_DEBUG DECLARE_IDTENTRY_IST #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 -- 2.7.4