From 6a8dfa8e4053adfcf02ee4d96287943064166beb Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 25 Feb 2020 23:33:30 +0100 Subject: [PATCH] x86/idtentry: Provide IDTENTRY_DF Provide a separate macro for #DF as this needs to emit paranoid only code and has also a special ASM stub in 32bit. Signed-off-by: Thomas Gleixner Reviewed-by: Alexandre Chartre Acked-by: Peter Zijlstra Acked-by: Andy Lutomirski Link: https://lkml.kernel.org/r/20200505135315.583415264@linutronix.de --- arch/x86/include/asm/idtentry.h | 87 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 87 insertions(+) diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index 060f9e3..9521f32 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -132,6 +132,35 @@ static __always_inline void __##func(struct pt_regs *regs, \ #define DEFINE_IDTENTRY_RAW(func) \ __visible noinstr void func(struct pt_regs *regs) +/** + * DECLARE_IDTENTRY_RAW_ERRORCODE - Declare functions for raw IDT entry points + * Error code pushed by hardware + * @vector: Vector number (ignored for C) + * @func: Function name of the entry point + * + * Maps to DECLARE_IDTENTRY_ERRORCODE() + */ +#define DECLARE_IDTENTRY_RAW_ERRORCODE(vector, func) \ + DECLARE_IDTENTRY_ERRORCODE(vector, func) + +/** + * DEFINE_IDTENTRY_RAW_ERRORCODE - Emit code for raw IDT entry points + * @func: Function name of the entry point + * + * @func is called from ASM entry code with interrupts disabled. + * + * The macro is written so it acts as function definition. Append the + * body with a pair of curly brackets. + * + * Contrary to DEFINE_IDTENTRY_ERRORCODE() this does not invoke the + * idtentry_enter/exit() helpers before and after the body invocation. This + * needs to be done in the body itself if applicable. Use if extra work + * is required before the enter/exit() helpers are invoked. + */ +#define DEFINE_IDTENTRY_RAW_ERRORCODE(func) \ +__visible noinstr void func(struct pt_regs *regs, unsigned long error_code) + + #ifdef CONFIG_X86_64 /** * DECLARE_IDTENTRY_IST - Declare functions for IST handling IDT entry points @@ -165,10 +194,58 @@ __visible noinstr void func(struct pt_regs *regs) #define DEFINE_IDTENTRY_NOIST(func) \ DEFINE_IDTENTRY_RAW(noist_##func) +/** + * DECLARE_IDTENTRY_DF - Declare functions for double fault + * @vector: Vector number (ignored for C) + * @func: Function name of the entry point + * + * Maps to DECLARE_IDTENTRY_RAW_ERRORCODE + */ +#define DECLARE_IDTENTRY_DF(vector, func) \ + DECLARE_IDTENTRY_RAW_ERRORCODE(vector, func) + +/** + * DEFINE_IDTENTRY_DF - Emit code for double fault + * @func: Function name of the entry point + * + * Maps to DEFINE_IDTENTRY_RAW_ERRORCODE + */ +#define DEFINE_IDTENTRY_DF(func) \ + DEFINE_IDTENTRY_RAW_ERRORCODE(func) + #else /* CONFIG_X86_64 */ + /* Maps to a regular IDTENTRY on 32bit for now */ # define DECLARE_IDTENTRY_IST DECLARE_IDTENTRY # define DEFINE_IDTENTRY_IST DEFINE_IDTENTRY + +/** + * DECLARE_IDTENTRY_DF - Declare functions for double fault 32bit variant + * @vector: Vector number (ignored for C) + * @func: Function name of the entry point + * + * Declares two functions: + * - The ASM entry point: asm_##func + * - The C handler called from the C shim + */ +#define DECLARE_IDTENTRY_DF(vector, func) \ + asmlinkage void asm_##func(void); \ + __visible void func(struct pt_regs *regs, \ + unsigned long error_code, \ + unsigned long address) + +/** + * DEFINE_IDTENTRY_DF - Emit code for double fault on 32bit + * @func: Function name of the entry point + * + * This is called through the doublefault shim which already provides + * cr2 in the address argument. + */ +#define DEFINE_IDTENTRY_DF(func) \ +__visible noinstr void func(struct pt_regs *regs, \ + unsigned long error_code, \ + unsigned long address) + #endif /* !CONFIG_X86_64 */ /* C-Code mapping */ @@ -212,6 +289,9 @@ __visible noinstr void func(struct pt_regs *regs) #define DECLARE_IDTENTRY_RAW(vector, func) \ DECLARE_IDTENTRY(vector, func) +#define DECLARE_IDTENTRY_RAW_ERRORCODE(vector, func) \ + DECLARE_IDTENTRY_ERRORCODE(vector, func) + #ifdef CONFIG_X86_64 # define DECLARE_IDTENTRY_MCE(vector, func) \ idtentry_mce_db vector asm_##func func @@ -219,12 +299,19 @@ __visible noinstr void func(struct pt_regs *regs) # define DECLARE_IDTENTRY_DEBUG(vector, func) \ idtentry_mce_db vector asm_##func func +# define DECLARE_IDTENTRY_DF(vector, func) \ + idtentry_df vector asm_##func func + #else # define DECLARE_IDTENTRY_MCE(vector, func) \ DECLARE_IDTENTRY(vector, func) # define DECLARE_IDTENTRY_DEBUG(vector, func) \ DECLARE_IDTENTRY(vector, func) + +/* No ASM emitted for DF as this goes through a C shim */ +# define DECLARE_IDTENTRY_DF(vector, func) + #endif /* No ASM code emitted for NMI */ -- 2.7.4