[tip: x86/entry] x86/entry: Convert Alignment check exception to IDTENTRY

tip-bot2 for Thomas Gleixner
2020-05-19T19:58:46Z

The following commit has been merged into the x86/entry branch of tip:

Commit-ID: ea28f3d0310506b97fdca160ea2e1e30e3bd4583
Gitweb: https://git.kernel.org/tip/ea28f3d0310506b97fdca160ea2e1e30e3bd4583
Author: Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Tue, 25 Feb 2020 23:16:28 +01:00
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Tue, 19 May 2020 16:04:03 +02:00

x86/entry: Convert Alignment check exception to IDTENTRY

Convert #AC to IDTENTRY_ERRORCODE:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
- Remove the RCU warning as the new entry macro ensures correctness

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505134905.928967113@linutronix.de

---
arch/x86/entry/entry_32.S | 6 ------
arch/x86/entry/entry_64.S | 1 -
arch/x86/include/asm/idtentry.h | 1 +
arch/x86/include/asm/traps.h | 3 ---
arch/x86/kernel/idt.c | 2 +-
arch/x86/kernel/traps.c | 4 +---
arch/x86/xen/enlighten_pv.c | 2 +-
arch/x86/xen/xen-asm_64.S | 2 +-
8 files changed, 5 insertions(+), 16 deletions(-)

diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index 66d4683..7402890 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -1311,12 +1311,6 @@ SYM_CODE_START(native_iret)
SYM_CODE_END(native_iret)
#endif

-SYM_CODE_START(alignment_check)
- ASM_CLAC
- pushl $do_alignment_check
- jmp common_exception
-SYM_CODE_END(alignment_check)
-
#ifdef CONFIG_X86_MCE
SYM_CODE_START(machine_check)
ASM_CLAC
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index f1f126b..3c95a63 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1073,7 +1073,6 @@ apicinterrupt IRQ_WORK_VECTOR irq_work_interrupt smp_irq_work_interrupt
*/

idtentry X86_TRAP_BP int3 do_int3 has_error_code=0
-idtentry X86_TRAP_AC alignment_check do_alignment_check has_error_code=1
idtentry X86_TRAP_XF simd_coprocessor_error do_simd_coprocessor_error has_error_code=0

idtentry X86_TRAP_PF page_fault do_page_fault has_error_code=1
diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h
index ed44ba6..531dbc0 100644
--- a/arch/x86/include/asm/idtentry.h
+++ b/arch/x86/include/asm/idtentry.h
@@ -137,5 +137,6 @@ DECLARE_IDTENTRY_ERRORCODE(X86_TRAP_TS, exc_invalid_tss);
DECLARE_IDTENTRY_ERRORCODE(X86_TRAP_NP, exc_segment_not_present);
DECLARE_IDTENTRY_ERRORCODE(X86_TRAP_SS, exc_stack_segment);
DECLARE_IDTENTRY_ERRORCODE(X86_TRAP_GP, exc_general_protection);
+DECLARE_IDTENTRY_ERRORCODE(X86_TRAP_AC, exc_alignment_check);

#endif
diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h
index e84677b..0f755e1 100644
--- a/arch/x86/include/asm/traps.h
+++ b/arch/x86/include/asm/traps.h
@@ -19,7 +19,6 @@ asmlinkage void double_fault(void);
#endif
asmlinkage void page_fault(void);
asmlinkage void async_page_fault(void);
-asmlinkage void alignment_check(void);
#ifdef CONFIG_X86_MCE
asmlinkage void machine_check(void);
#endif /* CONFIG_X86_MCE */
@@ -31,7 +30,6 @@ asmlinkage void xen_xendebug(void);
asmlinkage void xen_int3(void);
asmlinkage void xen_double_fault(void);
asmlinkage void xen_page_fault(void);
-asmlinkage void xen_alignment_check(void);
#ifdef CONFIG_X86_MCE
asmlinkage void xen_machine_check(void);
#endif /* CONFIG_X86_MCE */
@@ -43,7 +41,6 @@ dotraplinkage void do_nmi(struct pt_regs *regs, long error_code);
dotraplinkage void do_int3(struct pt_regs *regs, long error_code);
dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code, unsigned long cr2);
dotraplinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code, unsigned long address);
-dotraplinkage void do_alignment_check(struct pt_regs *regs, long error_code);
dotraplinkage void do_simd_coprocessor_error(struct pt_regs *regs, long error_code);
#ifdef CONFIG_X86_32
dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code);
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index 2bde50d..af48196 100644
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -85,7 +85,7 @@ static const __initconst struct idt_data def_idts[] = {
INTG(X86_TRAP_GP, asm_exc_general_protection),
INTG(X86_TRAP_SPURIOUS, asm_exc_spurious_interrupt_bug),
INTG(X86_TRAP_MF, asm_exc_coprocessor_error),
- INTG(X86_TRAP_AC, alignment_check),
+ INTG(X86_TRAP_AC, asm_exc_alignment_check),
INTG(X86_TRAP_XF, simd_coprocessor_error),

#ifdef CONFIG_X86_32
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index ba26beb..9f156c8 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -270,12 +270,10 @@ DEFINE_IDTENTRY_ERRORCODE(exc_stack_segment)
0, NULL);
}

-dotraplinkage void do_alignment_check(struct pt_regs *regs, long error_code)
+DEFINE_IDTENTRY_ERRORCODE(exc_alignment_check)
{
char *str = "alignment check";

- RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
-
if (notify_die(DIE_TRAP, str, regs, error_code, X86_TRAP_AC, SIGBUS) == NOTIFY_STOP)
return;

diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 6225d1f..afe12d9 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -634,7 +634,7 @@ static struct trap_array_entry trap_array[] = {
TRAP_ENTRY(exc_general_protection, false ),
TRAP_ENTRY(exc_spurious_interrupt_bug, false ),
TRAP_ENTRY(exc_coprocessor_error, false ),
- { alignment_check, xen_alignment_check, false },
+ TRAP_ENTRY(exc_alignment_check, false ),
{ simd_coprocessor_error, xen_simd_coprocessor_error, false },
};

diff --git a/arch/x86/xen/xen-asm_64.S b/arch/x86/xen/xen-asm_64.S
index 589de18..a591bec 100644
--- a/arch/x86/xen/xen-asm_64.S
+++ b/arch/x86/xen/xen-asm_64.S
@@ -46,7 +46,7 @@ xen_pv_trap asm_exc_general_protection
xen_pv_trap page_fault
xen_pv_trap asm_exc_spurious_interrupt_bug
xen_pv_trap asm_exc_coprocessor_error
-xen_pv_trap alignment_check
+xen_pv_trap asm_exc_alignment_check
#ifdef CONFIG_X86_MCE
xen_pv_trap machine_check
#endif /* CONFIG_X86_MCE */