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Message-Id: <20230804075734.8372-1-xin3.li@intel.com>
Date: Fri, 4 Aug 2023 00:57:34 -0700
From: Xin Li <xin3.li@...el.com>
To: linux-kernel@...r.kernel.org, xen-devel@...ts.xenproject.org
Cc: Andy Lutomirski <luto@...nel.org>,
Thomas Gleixner <tglx@...utronix.de>,
Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
Dave Hansen <dave.hansen@...ux.intel.com>, x86@...nel.org,
"H . Peter Anvin" <hpa@...or.com>,
Peter Zijlstra <peterz@...radead.org>,
Juergen Gross <jgross@...e.com>,
Boris Ostrovsky <boris.ostrovsky@...cle.com>
Subject: [RFC PATCH 1/1] x86/traps: Get rid of exception handlers' second argument error code
The IDT event delivery of X86_TRAP_DF, X86_TRAP_TS, X86_TRAP_NP,
X86_TRAP_SS, X86_TRAP_GP, X86_TRAP_AC and X86_TRAP_CP pushes an error
code into the orig_ax member of the pt_regs structure, and the error
code is passed as the second argument of their C-handlers, although
the pt_regs structure is already passed as the first argument.
The asm entry code of such faults does the following
movq ORIG_RAX(%rsp), %rsi /* get error code into 2nd argument*/
movq $-1, ORIG_RAX(%rsp) /* no syscall to restart */
to set the orig_ax member to -1 just before calling the C-handler.
In addition, the IRQ entry code uses the second error code argument
as its IRQ vector, as the IRQ asm entry code pushes its IRQ vector
into the orig_ax member.
The commit d99015b1abbad ("x86: move entry_64.S register saving out of
the macros") introduced the changes to set orig_ax to -1, but I can't
see why it's required. Our tests on x86_64 and x86_32 seem fine if
orig_ax is left unchanged instead of set to -1.
It's probably cleaner and simpler to remove the second argument from
such C-handlers while leave orig_ax unchanged to pass the error code
inside the first argument. This patch allows FRED to use IDT exception
and IRQ handlers with no or minimal changes.
The DECLARE_IDTENTRY_*_ERRORCODE macros still need to be kept to emit
the ASM stubs, which do NOT need to push -1 as an error code placement.
As a result, their corresponding DEFINE_IDTENTRY_*_ERRORCODE macros
are kept, although they simply mapped to their no _ERRORCODE suffix
versions.
I haven't checked Xen implications with this change, i.e., does Xen
hypervisor need to adjust how it passes arguments to PV guests?
Signed-off-by: Xin Li <xin3.li@...el.com>
---
arch/x86/entry/common.c | 2 +-
arch/x86/entry/entry_32.S | 7 --
arch/x86/entry/entry_64.S | 22 ++-----
arch/x86/include/asm/idtentry.h | 108 ++++++++++---------------------
arch/x86/include/asm/irq_stack.h | 43 ++----------
arch/x86/kernel/apic/apic.c | 2 +-
arch/x86/kernel/doublefault_32.c | 2 +-
arch/x86/kernel/irq.c | 1 +
arch/x86/kernel/sev.c | 10 +--
arch/x86/kernel/traps.c | 14 ++--
arch/x86/mm/fault.c | 6 +-
arch/x86/xen/enlighten_pv.c | 2 +-
12 files changed, 69 insertions(+), 150 deletions(-)
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index 6c2826417b33..83d31cd82a65 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -305,7 +305,7 @@ __visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs)
bool inhcall;
instrumentation_begin();
- run_sysvec_on_irqstack_cond(__xen_pv_evtchn_do_upcall, regs);
+ run_irq_on_irqstack_cond(__xen_pv_evtchn_do_upcall, regs);
inhcall = get_and_clear_inhcall();
if (inhcall && !WARN_ON_ONCE(state.exit_rcu)) {
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index 6e6af42e044a..41345b0d9bb8 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -642,8 +642,6 @@ SYM_CODE_START_LOCAL(asm_\cfunc)
SAVE_ALL switch_stacks=1
ENCODE_FRAME_POINTER
movl %esp, %eax
- movl PT_ORIG_EAX(%esp), %edx /* get the vector from stack */
- movl $-1, PT_ORIG_EAX(%esp) /* no syscall to restart */
call \cfunc
jmp handle_exception_return
SYM_CODE_END(asm_\cfunc)
@@ -1036,11 +1034,6 @@ SYM_CODE_START_LOCAL_NOALIGN(handle_exception)
ENCODE_FRAME_POINTER
movl PT_GS(%esp), %edi # get the function address
-
- /* fixup orig %eax */
- movl PT_ORIG_EAX(%esp), %edx # get the error code
- movl $-1, PT_ORIG_EAX(%esp) # no syscall to restart
-
movl %esp, %eax # pt_regs pointer
CALL_NOSPEC edi
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 43606de22511..ddfa0e7b8485 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -337,9 +337,8 @@ SYM_CODE_END(xen_error_entry)
/**
* idtentry_body - Macro to emit code calling the C function
* @cfunc: C function to be called
- * @has_error_code: Hardware pushed error code on stack
*/
-.macro idtentry_body cfunc has_error_code:req
+.macro idtentry_body cfunc
/*
* Call error_entry() and switch to the task stack if from userspace.
@@ -356,12 +355,6 @@ SYM_CODE_END(xen_error_entry)
UNWIND_HINT_REGS
movq %rsp, %rdi /* pt_regs pointer into 1st argument*/
-
- .if \has_error_code == 1
- movq ORIG_RAX(%rsp), %rsi /* get error code into 2nd argument*/
- movq $-1, ORIG_RAX(%rsp) /* no syscall to restart */
- .endif
-
call \cfunc
/* For some configurations \cfunc ends up being a noreturn. */
@@ -412,7 +405,7 @@ SYM_CODE_START(\asmsym)
.Lfrom_usermode_no_gap_\@:
.endif
- idtentry_body \cfunc \has_error_code
+ idtentry_body \cfunc
_ASM_NOKPROBE(\asmsym)
SYM_CODE_END(\asmsym)
@@ -485,7 +478,7 @@ SYM_CODE_START(\asmsym)
/* Switch to the regular task stack and use the noist entry point */
.Lfrom_usermode_switch_stack_\@:
- idtentry_body noist_\cfunc, has_error_code=0
+ idtentry_body noist_\cfunc
_ASM_NOKPROBE(\asmsym)
SYM_CODE_END(\asmsym)
@@ -548,12 +541,7 @@ SYM_CODE_START(\asmsym)
ENCODE_FRAME_POINTER
UNWIND_HINT_REGS
- /* Update pt_regs */
- movq ORIG_RAX(%rsp), %rsi /* get error code into 2nd argument*/
- movq $-1, ORIG_RAX(%rsp) /* no syscall to restart */
-
movq %rsp, %rdi /* pt_regs pointer */
-
call kernel_\cfunc
/*
@@ -565,7 +553,7 @@ SYM_CODE_START(\asmsym)
/* Switch to the regular task stack */
.Lfrom_usermode_switch_stack_\@:
- idtentry_body user_\cfunc, has_error_code=1
+ idtentry_body user_\cfunc
_ASM_NOKPROBE(\asmsym)
SYM_CODE_END(\asmsym)
@@ -589,8 +577,6 @@ SYM_CODE_START(\asmsym)
UNWIND_HINT_REGS
movq %rsp, %rdi /* pt_regs pointer into first argument */
- movq ORIG_RAX(%rsp), %rsi /* get error code into 2nd argument*/
- movq $-1, ORIG_RAX(%rsp) /* no syscall to restart */
call \cfunc
/* For some configurations \cfunc ends up being a noreturn. */
diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h
index b241af4ce9b4..7e0e9f8bc8ab 100644
--- a/arch/x86/include/asm/idtentry.h
+++ b/arch/x86/include/asm/idtentry.h
@@ -15,7 +15,7 @@
/**
* DECLARE_IDTENTRY - Declare functions for simple IDT entry points
- * No error code pushed by hardware
+ * An error code may be pushed by hardware
* @vector: Vector number (ignored for C)
* @func: Function name of the entry point
*
@@ -76,42 +76,25 @@ static __always_inline void __##func(struct pt_regs *regs)
* - The XEN PV trap entry point: xen_##func (maybe unused)
* - The C handler called from the ASM entry point
*
- * Same as DECLARE_IDTENTRY, but has an extra error_code argument for the
- * C-handler.
+ * Same as DECLARE_IDTENTRY(), but required for emitting the ASM stubs, which
+ * do NOT need to push -1 as an error code placement.
*/
#define DECLARE_IDTENTRY_ERRORCODE(vector, func) \
- asmlinkage void asm_##func(void); \
- asmlinkage void xen_asm_##func(void); \
- __visible void func(struct pt_regs *regs, unsigned long error_code)
+ DECLARE_IDTENTRY(vector, func)
/**
* DEFINE_IDTENTRY_ERRORCODE - Emit code for simple IDT entry points
* Error code pushed by hardware
* @func: Function name of the entry point
*
- * Same as DEFINE_IDTENTRY, but has an extra error_code argument
+ * Same as DEFINE_IDTENTRY().
*/
#define DEFINE_IDTENTRY_ERRORCODE(func) \
-static __always_inline void __##func(struct pt_regs *regs, \
- unsigned long error_code); \
- \
-__visible noinstr void func(struct pt_regs *regs, \
- unsigned long error_code) \
-{ \
- irqentry_state_t state = irqentry_enter(regs); \
- \
- instrumentation_begin(); \
- __##func (regs, error_code); \
- instrumentation_end(); \
- irqentry_exit(regs, state); \
-} \
- \
-static __always_inline void __##func(struct pt_regs *regs, \
- unsigned long error_code)
+ DEFINE_IDTENTRY(func)
/**
* DECLARE_IDTENTRY_RAW - Declare functions for raw IDT entry points
- * No error code pushed by hardware
+ * An error code may be pushed by hardware
* @vector: Vector number (ignored for C)
* @func: Function name of the entry point
*
@@ -135,7 +118,7 @@ static __always_inline void __##func(struct pt_regs *regs, \
* is required before the enter/exit() helpers are invoked.
*/
#define DEFINE_IDTENTRY_RAW(func) \
-__visible noinstr void func(struct pt_regs *regs)
+ __visible noinstr void func(struct pt_regs *regs)
/**
* DECLARE_IDTENTRY_RAW_ERRORCODE - Declare functions for raw IDT entry points
@@ -143,7 +126,8 @@ __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_ERRORCODE()
+ * Maps to DECLARE_IDTENTRY_ERRORCODE() for emitting the ASM stubs, which
+ * do NOT need to push -1 as an error code placement
*/
#define DECLARE_IDTENTRY_RAW_ERRORCODE(vector, func) \
DECLARE_IDTENTRY_ERRORCODE(vector, func)
@@ -157,13 +141,10 @@ __visible noinstr void func(struct pt_regs *regs)
* 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
- * irqentry_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.
+ * Same as DEFINE_IDTENTRY_RAW().
*/
#define DEFINE_IDTENTRY_RAW_ERRORCODE(func) \
-__visible noinstr void func(struct pt_regs *regs, unsigned long error_code)
+ DEFINE_IDTENTRY_RAW(func)
/**
* DECLARE_IDTENTRY_IRQ - Declare functions for device interrupt IDT entry
@@ -171,40 +152,37 @@ __visible noinstr void func(struct pt_regs *regs, unsigned long error_code)
* @vector: Vector number (ignored for C)
* @func: Function name of the entry point
*
- * Maps to DECLARE_IDTENTRY_ERRORCODE()
+ * Maps to DECLARE_IDTENTRY().
*/
#define DECLARE_IDTENTRY_IRQ(vector, func) \
- DECLARE_IDTENTRY_ERRORCODE(vector, func)
+ DECLARE_IDTENTRY(vector, func)
/**
* DEFINE_IDTENTRY_IRQ - Emit code for device interrupt IDT entry points
* @func: Function name of the entry point
*
- * The vector number is pushed by the low level entry stub and handed
- * to the function as error_code argument which needs to be truncated
- * to an u8 because the push is sign extending.
+ * The vector number is pushed by the low level entry stub into the orig_ax
+ * member of the pt_regs structure passed as the only argument.
*
* irq_enter/exit_rcu() are invoked before the function body and the
* KVM L1D flush request is set. Stack switching to the interrupt stack
* has to be done in the function body if necessary.
*/
#define DEFINE_IDTENTRY_IRQ(func) \
-static void __##func(struct pt_regs *regs, u32 vector); \
+static void __##func(struct pt_regs *regs); \
\
-__visible noinstr void func(struct pt_regs *regs, \
- unsigned long error_code) \
+__visible noinstr void func(struct pt_regs *regs) \
{ \
irqentry_state_t state = irqentry_enter(regs); \
- u32 vector = (u32)(u8)error_code; \
\
instrumentation_begin(); \
kvm_set_cpu_l1tf_flush_l1d(); \
- run_irq_on_irqstack_cond(__##func, regs, vector); \
+ run_irq_on_irqstack_cond(__##func, regs); \
instrumentation_end(); \
irqentry_exit(regs, state); \
} \
\
-static noinline void __##func(struct pt_regs *regs, u32 vector)
+static noinline void __##func(struct pt_regs *regs)
/**
* DECLARE_IDTENTRY_SYSVEC - Declare functions for system vector entry points
@@ -225,26 +203,10 @@ static noinline void __##func(struct pt_regs *regs, u32 vector)
* DEFINE_IDTENTRY_SYSVEC - Emit code for system vector IDT entry points
* @func: Function name of the entry point
*
- * irqentry_enter/exit() and irq_enter/exit_rcu() are invoked before the
- * function body. KVM L1D flush request is set.
- *
- * Runs the function on the interrupt stack if the entry hit kernel mode
+ * Maps to DEFINE_IDTENTRY_IRQ().
*/
#define DEFINE_IDTENTRY_SYSVEC(func) \
-static void __##func(struct pt_regs *regs); \
- \
-__visible noinstr void func(struct pt_regs *regs) \
-{ \
- irqentry_state_t state = irqentry_enter(regs); \
- \
- instrumentation_begin(); \
- kvm_set_cpu_l1tf_flush_l1d(); \
- run_sysvec_on_irqstack_cond(__##func, regs); \
- instrumentation_end(); \
- irqentry_exit(regs, state); \
-} \
- \
-static noinline void __##func(struct pt_regs *regs)
+ DEFINE_IDTENTRY_IRQ(func)
/**
* DEFINE_IDTENTRY_SYSVEC_SIMPLE - Emit code for simple system vector IDT
@@ -297,8 +259,8 @@ static __always_inline void __##func(struct pt_regs *regs)
* @vector: Vector number (ignored for C)
* @func: Function name of the entry point
*
- * Maps to DECLARE_IDTENTRY_RAW, but declares also the NOIST C handler
- * which is called from the ASM entry point on user mode entry
+ * 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); \
@@ -309,19 +271,19 @@ static __always_inline void __##func(struct pt_regs *regs)
* @vector: Vector number (ignored for C)
* @func: Function name of the entry point
*
- * Maps to DECLARE_IDTENTRY_RAW_ERRORCODE, but declares also the
+ * Maps to DECLARE_IDTENTRY_RAW_ERRORCODE(), but declares also the
* safe_stack C handler.
*/
#define DECLARE_IDTENTRY_VC(vector, func) \
DECLARE_IDTENTRY_RAW_ERRORCODE(vector, func); \
- __visible noinstr void kernel_##func(struct pt_regs *regs, unsigned long error_code); \
- __visible noinstr void user_##func(struct pt_regs *regs, unsigned long error_code)
+ __visible noinstr void kernel_##func(struct pt_regs *regs); \
+ __visible noinstr void user_##func(struct pt_regs *regs)
/**
* DEFINE_IDTENTRY_IST - Emit code for IST entry points
* @func: Function name of the entry point
*
- * Maps to DEFINE_IDTENTRY_RAW
+ * Maps to DEFINE_IDTENTRY_RAW().
*/
#define DEFINE_IDTENTRY_IST(func) \
DEFINE_IDTENTRY_RAW(func)
@@ -342,7 +304,7 @@ static __always_inline void __##func(struct pt_regs *regs)
* @vector: Vector number (ignored for C)
* @func: Function name of the entry point
*
- * Maps to DECLARE_IDTENTRY_RAW_ERRORCODE
+ * Maps to DECLARE_IDTENTRY_RAW_ERRORCODE().
*/
#define DECLARE_IDTENTRY_DF(vector, func) \
DECLARE_IDTENTRY_RAW_ERRORCODE(vector, func)
@@ -351,7 +313,7 @@ static __always_inline void __##func(struct pt_regs *regs)
* DEFINE_IDTENTRY_DF - Emit code for double fault
* @func: Function name of the entry point
*
- * Maps to DEFINE_IDTENTRY_RAW_ERRORCODE
+ * Maps to DEFINE_IDTENTRY_RAW_ERRORCODE().
*/
#define DEFINE_IDTENTRY_DF(func) \
DEFINE_IDTENTRY_RAW_ERRORCODE(func)
@@ -361,9 +323,9 @@ static __always_inline void __##func(struct pt_regs *regs)
when raised from kernel mode
* @func: Function name of the entry point
*
- * Maps to DEFINE_IDTENTRY_RAW_ERRORCODE
+ * Maps to DEFINE_IDTENTRY_RAW_ERRORCODE().
*/
-#define DEFINE_IDTENTRY_VC_KERNEL(func) \
+#define DEFINE_IDTENTRY_VC_KERNEL(func) \
DEFINE_IDTENTRY_RAW_ERRORCODE(kernel_##func)
/**
@@ -371,9 +333,9 @@ static __always_inline void __##func(struct pt_regs *regs)
when raised from user mode
* @func: Function name of the entry point
*
- * Maps to DEFINE_IDTENTRY_RAW_ERRORCODE
+ * Maps to DEFINE_IDTENTRY_RAW_ERRORCODE().
*/
-#define DEFINE_IDTENTRY_VC_USER(func) \
+#define DEFINE_IDTENTRY_VC_USER(func) \
DEFINE_IDTENTRY_RAW_ERRORCODE(user_##func)
#else /* CONFIG_X86_64 */
@@ -390,7 +352,6 @@ static __always_inline void __##func(struct pt_regs *regs)
#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)
/**
@@ -402,7 +363,6 @@ static __always_inline void __##func(struct pt_regs *regs)
*/
#define DEFINE_IDTENTRY_DF(func) \
__visible noinstr void func(struct pt_regs *regs, \
- unsigned long error_code, \
unsigned long address)
#endif /* !CONFIG_X86_64 */
diff --git a/arch/x86/include/asm/irq_stack.h b/arch/x86/include/asm/irq_stack.h
index 798183867d78..d04186267e26 100644
--- a/arch/x86/include/asm/irq_stack.h
+++ b/arch/x86/include/asm/irq_stack.h
@@ -153,7 +153,7 @@
}
/*
- * Function call sequence for __call_on_irqstack() for system vectors.
+ * Function call sequence for __call_on_irqstack() for IRQs.
*
* Note that irq_enter_rcu() and irq_exit_rcu() do not use the input
* mechanism because these functions are global and cannot be optimized out
@@ -166,41 +166,20 @@
* call to idtentry_exit() anyway, it's likely that it does not cause extra
* effort for this asm magic.
*/
-#define ASM_CALL_SYSVEC \
+#define ASM_CALL_IRQ \
"call irq_enter_rcu \n" \
ASM_CALL_ARG1 \
"call irq_exit_rcu \n"
-#define SYSVEC_CONSTRAINTS , [arg1] "r" (regs)
+#define IRQ_CONSTRAINTS , [arg1] "r" (regs)
-#define run_sysvec_on_irqstack_cond(func, regs) \
+#define run_irq_on_irqstack_cond(func, regs) \
{ \
assert_function_type(func, void (*)(struct pt_regs *)); \
assert_arg_type(regs, struct pt_regs *); \
\
- call_on_irqstack_cond(func, regs, ASM_CALL_SYSVEC, \
- SYSVEC_CONSTRAINTS, regs); \
-}
-
-/*
- * As in ASM_CALL_SYSVEC above the clobbers force the compiler to store
- * @regs and @vector in callee saved registers.
- */
-#define ASM_CALL_IRQ \
- "call irq_enter_rcu \n" \
- ASM_CALL_ARG2 \
- "call irq_exit_rcu \n"
-
-#define IRQ_CONSTRAINTS , [arg1] "r" (regs), [arg2] "r" ((unsigned long)vector)
-
-#define run_irq_on_irqstack_cond(func, regs, vector) \
-{ \
- assert_function_type(func, void (*)(struct pt_regs *, u32)); \
- assert_arg_type(regs, struct pt_regs *); \
- assert_arg_type(vector, u32); \
- \
call_on_irqstack_cond(func, regs, ASM_CALL_IRQ, \
- IRQ_CONSTRAINTS, regs, vector); \
+ IRQ_CONSTRAINTS, regs); \
}
#ifdef CONFIG_SOFTIRQ_ON_OWN_STACK
@@ -220,22 +199,14 @@
#endif
#else /* CONFIG_X86_64 */
-/* System vector handlers always run on the stack they interrupted. */
-#define run_sysvec_on_irqstack_cond(func, regs) \
+/* always run on the stack they interrupted. */
+#define run_irq_on_irqstack_cond(func, regs) \
{ \
irq_enter_rcu(); \
func(regs); \
irq_exit_rcu(); \
}
-/* Switches to the irq stack within func() */
-#define run_irq_on_irqstack_cond(func, regs, vector) \
-{ \
- irq_enter_rcu(); \
- func(regs, vector); \
- irq_exit_rcu(); \
-}
-
#endif /* !CONFIG_X86_64 */
#endif
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index af49e24b46a4..af3170239b2e 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2230,7 +2230,7 @@ static noinline void handle_spurious_interrupt(u8 vector)
*/
DEFINE_IDTENTRY_IRQ(spurious_interrupt)
{
- handle_spurious_interrupt(vector);
+ handle_spurious_interrupt((u32)(u8)regs->orig_ax);
}
DEFINE_IDTENTRY_SYSVEC(sysvec_spurious_apic_interrupt)
diff --git a/arch/x86/kernel/doublefault_32.c b/arch/x86/kernel/doublefault_32.c
index 6eaf9a6bc02f..f2d635290034 100644
--- a/arch/x86/kernel/doublefault_32.c
+++ b/arch/x86/kernel/doublefault_32.c
@@ -70,7 +70,7 @@ asmlinkage noinstr void __noreturn doublefault_shim(void)
regs.cx = TSS(cx);
regs.bx = TSS(bx);
- exc_double_fault(®s, 0, cr2);
+ exc_double_fault(®s, cr2);
/*
* x86_32 does not save the original CR3 anywhere on a task switch.
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 9f668d2f3d11..be1d8aeabdde 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -246,6 +246,7 @@ static __always_inline void handle_irq(struct irq_desc *desc,
*/
DEFINE_IDTENTRY_IRQ(common_interrupt)
{
+ u32 vector = (u32)(u8)regs->orig_ax;
struct pt_regs *old_regs = set_irq_regs(regs);
struct irq_desc *desc;
diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c
index 1ee7bed453de..34432c1c52ee 100644
--- a/arch/x86/kernel/sev.c
+++ b/arch/x86/kernel/sev.c
@@ -1773,24 +1773,23 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
static __always_inline void vc_forward_exception(struct es_em_ctxt *ctxt)
{
- long error_code = ctxt->fi.error_code;
int trapnr = ctxt->fi.vector;
ctxt->regs->orig_ax = ctxt->fi.error_code;
switch (trapnr) {
case X86_TRAP_GP:
- exc_general_protection(ctxt->regs, error_code);
+ exc_general_protection(ctxt->regs);
break;
case X86_TRAP_UD:
exc_invalid_op(ctxt->regs);
break;
case X86_TRAP_PF:
write_cr2(ctxt->fi.cr2);
- exc_page_fault(ctxt->regs, error_code);
+ exc_page_fault(ctxt->regs);
break;
case X86_TRAP_AC:
- exc_alignment_check(ctxt->regs, error_code);
+ exc_alignment_check(ctxt->regs);
break;
default:
pr_emerg("Unsupported exception in #VC instruction emulation - can't continue\n");
@@ -1885,6 +1884,7 @@ static __always_inline bool vc_is_db(unsigned long error_code)
*/
DEFINE_IDTENTRY_VC_KERNEL(exc_vmm_communication)
{
+ unsigned long error_code = regs->orig_ax;
irqentry_state_t irq_state;
/*
@@ -1937,6 +1937,8 @@ DEFINE_IDTENTRY_VC_KERNEL(exc_vmm_communication)
*/
DEFINE_IDTENTRY_VC_USER(exc_vmm_communication)
{
+ unsigned long error_code = regs->orig_ax;
+
/*
* Handle #DB before calling into !noinstr code to avoid recursive #DB.
*/
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 4a817d20ce3b..26d023560d03 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -233,6 +233,8 @@ enum cp_error_code {
DEFINE_IDTENTRY_ERRORCODE(exc_control_protection)
{
+ unsigned long error_code = regs->orig_ax;
+
if (!cpu_feature_enabled(X86_FEATURE_IBT)) {
pr_err("Unexpected #CP\n");
BUG();
@@ -360,24 +362,25 @@ DEFINE_IDTENTRY(exc_coproc_segment_overrun)
DEFINE_IDTENTRY_ERRORCODE(exc_invalid_tss)
{
- do_error_trap(regs, error_code, "invalid TSS", X86_TRAP_TS, SIGSEGV,
+ do_error_trap(regs, regs->orig_ax, "invalid TSS", X86_TRAP_TS, SIGSEGV,
0, NULL);
}
DEFINE_IDTENTRY_ERRORCODE(exc_segment_not_present)
{
- do_error_trap(regs, error_code, "segment not present", X86_TRAP_NP,
+ do_error_trap(regs, regs->orig_ax, "segment not present", X86_TRAP_NP,
SIGBUS, 0, NULL);
}
DEFINE_IDTENTRY_ERRORCODE(exc_stack_segment)
{
- do_error_trap(regs, error_code, "stack segment", X86_TRAP_SS, SIGBUS,
+ do_error_trap(regs, regs->orig_ax, "stack segment", X86_TRAP_SS, SIGBUS,
0, NULL);
}
DEFINE_IDTENTRY_ERRORCODE(exc_alignment_check)
{
+ unsigned long error_code = regs->orig_ax;
char *str = "alignment check";
if (notify_die(DIE_TRAP, str, regs, error_code, X86_TRAP_AC, SIGBUS) == NOTIFY_STOP)
@@ -436,6 +439,7 @@ __visible void __noreturn handle_stack_overflow(struct pt_regs *regs,
*/
DEFINE_IDTENTRY_DF(exc_double_fault)
{
+ unsigned long error_code = regs->orig_ax;
static const char str[] = "double fault";
struct task_struct *tsk = current;
@@ -728,6 +732,7 @@ static void gp_user_force_sig_segv(struct pt_regs *regs, int trapnr,
DEFINE_IDTENTRY_ERRORCODE(exc_general_protection)
{
+ unsigned long error_code = regs->orig_ax;
char desc[sizeof(GPFSTR) + 50 + 2*sizeof(unsigned long) + 1] = GPFSTR;
enum kernel_gp_hint hint = GP_NO_HINT;
unsigned long gp_addr;
@@ -1254,7 +1259,8 @@ DEFINE_IDTENTRY(exc_simd_coprocessor_error)
if (IS_ENABLED(CONFIG_X86_INVD_BUG)) {
/* AMD 486 bug: INVD in CPL 0 raises #XF instead of #GP */
if (!static_cpu_has(X86_FEATURE_XMM)) {
- __exc_general_protection(regs, 0);
+ regs->orig_ax = 0;
+ __exc_general_protection(regs);
return;
}
}
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index e8711b2cafaf..c821ea389194 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -1471,9 +1471,9 @@ trace_page_fault_entries(struct pt_regs *regs, unsigned long error_code,
}
static __always_inline void
-handle_page_fault(struct pt_regs *regs, unsigned long error_code,
- unsigned long address)
+handle_page_fault(struct pt_regs *regs, unsigned long address)
{
+ unsigned long error_code = regs->orig_ax;
trace_page_fault_entries(regs, error_code, address);
if (unlikely(kmmio_fault(regs, address)))
@@ -1539,7 +1539,7 @@ DEFINE_IDTENTRY_RAW_ERRORCODE(exc_page_fault)
state = irqentry_enter(regs);
instrumentation_begin();
- handle_page_fault(regs, error_code, address);
+ handle_page_fault(regs, address);
instrumentation_end();
irqentry_exit(regs, state);
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 93b658248d01..929d56acd033 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -614,7 +614,7 @@ DEFINE_IDTENTRY_RAW(xenpv_exc_nmi)
DEFINE_IDTENTRY_RAW_ERRORCODE(xenpv_exc_double_fault)
{
/* On Xen PV, DF doesn't use IST. The C part is the same as native. */
- exc_double_fault(regs, error_code);
+ exc_double_fault(regs);
}
DEFINE_IDTENTRY_RAW(xenpv_exc_debug)
--
2.34.1
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