[tip: x86/entry] x86/entry: Convert Overflow exception to IDTENTRY

tip-bot2 for Thomas Gleixner
2020-05-19T19:59:06Z

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

Commit-ID: 50455f27bae20453b4042423dc5ec1bee9ef89f5
Gitweb: https://git.kernel.org/tip/50455f27bae20453b4042423dc5ec1bee9ef89f5
Author: Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Tue, 25 Feb 2020 23:16:15 +01:00
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Tue, 19 May 2020 16:03:58 +02:00

x86/entry: Convert Overflow exception to IDTENTRY

Convert #OF to IDTENTRY:
- 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

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134904.771457898@linutronix.de

---
arch/x86/entry/entry_32.S | 7 -------
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 | 6 +++++-
arch/x86/xen/enlighten_pv.c | 2 +-
arch/x86/xen/xen-asm_64.S | 2 +-
8 files changed, 9 insertions(+), 15 deletions(-)

diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index 398fd3c..e5d57f6 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -1325,13 +1325,6 @@ SYM_CODE_START(native_iret)
SYM_CODE_END(native_iret)
#endif

-SYM_CODE_START(overflow)
- ASM_CLAC
- pushl $0
- pushl $do_overflow
- jmp common_exception
-SYM_CODE_END(overflow)
-
SYM_CODE_START(bounds)
ASM_CLAC
pushl $0
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index e18594d..eb503b0 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1072,7 +1072,6 @@ apicinterrupt IRQ_WORK_VECTOR irq_work_interrupt smp_irq_work_interrupt
* Exception entry points.
*/

-idtentry X86_TRAP_OF overflow do_overflow has_error_code=0
idtentry X86_TRAP_BP int3 do_int3 has_error_code=0
idtentry X86_TRAP_BR bounds do_bounds has_error_code=0
idtentry X86_TRAP_UD invalid_op do_invalid_op has_error_code=0
diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h
index e6f6e29..54c41b3 100644
--- a/arch/x86/include/asm/idtentry.h
+++ b/arch/x86/include/asm/idtentry.h
@@ -78,5 +78,6 @@ static __always_inline void __##func(struct pt_regs *regs)

/* Simple exception entry points. No hardware error code */
DECLARE_IDTENTRY(X86_TRAP_DE, exc_divide_error);
+DECLARE_IDTENTRY(X86_TRAP_OF, exc_overflow);

#endif
diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h
index e68cbf8..1b0452c 100644
--- a/arch/x86/include/asm/traps.h
+++ b/arch/x86/include/asm/traps.h
@@ -14,7 +14,6 @@
asmlinkage void debug(void);
asmlinkage void nmi(void);
asmlinkage void int3(void);
-asmlinkage void overflow(void);
asmlinkage void bounds(void);
asmlinkage void invalid_op(void);
asmlinkage void device_not_available(void);
@@ -40,7 +39,6 @@ asmlinkage void simd_coprocessor_error(void);
asmlinkage void xen_xennmi(void);
asmlinkage void xen_xendebug(void);
asmlinkage void xen_int3(void);
-asmlinkage void xen_overflow(void);
asmlinkage void xen_bounds(void);
asmlinkage void xen_invalid_op(void);
asmlinkage void xen_device_not_available(void);
@@ -63,7 +61,6 @@ asmlinkage void xen_simd_coprocessor_error(void);
dotraplinkage void do_debug(struct pt_regs *regs, long error_code);
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_overflow(struct pt_regs *regs, long error_code);
dotraplinkage void do_bounds(struct pt_regs *regs, long error_code);
dotraplinkage void do_invalid_op(struct pt_regs *regs, long error_code);
dotraplinkage void do_device_not_available(struct pt_regs *regs, long error_code);
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index f2a751b..f8d7962 100644
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -99,7 +99,7 @@ static const __initconst struct idt_data def_idts[] = {
INTG(X86_TRAP_MC, machine_check),
#endif

- SYSG(X86_TRAP_OF, overflow),
+ SYSG(X86_TRAP_OF, asm_exc_overflow),
#if defined(CONFIG_IA32_EMULATION)
SYSG(IA32_SYSCALL_VECTOR, entry_INT80_compat),
#elif defined(CONFIG_X86_32)
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 37092f7..b522e2a 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -226,6 +226,11 @@ DEFINE_IDTENTRY(exc_divide_error)
FPE_INTDIV, error_get_trap_addr(regs));
}

+DEFINE_IDTENTRY(exc_overflow)
+{
+ do_error_trap(regs, 0, "overflow", X86_TRAP_OF, SIGSEGV, 0, NULL);
+}
+
#define IP ((void __user *)uprobe_get_trap_addr(regs))
#define DO_ERROR(trapnr, signr, sicode, addr, str, name) \
dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \
@@ -233,7 +238,6 @@ dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \
do_error_trap(regs, error_code, str, trapnr, signr, sicode, addr); \
}

-DO_ERROR(X86_TRAP_OF, SIGSEGV, 0, NULL, "overflow", overflow)
DO_ERROR(X86_TRAP_UD, SIGILL, ILL_ILLOPN, IP, "invalid opcode", invalid_op)
DO_ERROR(X86_TRAP_OLD_MF, SIGFPE, 0, NULL, "coprocessor segment overrun", coprocessor_segment_overrun)
DO_ERROR(X86_TRAP_TS, SIGSEGV, 0, NULL, "invalid TSS", invalid_TSS)
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index c2fe7b6..f5487e5 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -618,7 +618,7 @@ static struct trap_array_entry trap_array[] = {
#endif
{ nmi, xen_xennmi, true },
{ int3, xen_int3, false },
- { overflow, xen_overflow, false },
+ TRAP_ENTRY(exc_overflow, false ),
#ifdef CONFIG_IA32_EMULATION
{ entry_INT80_compat, xen_entry_INT80_compat, false },
#endif
diff --git a/arch/x86/xen/xen-asm_64.S b/arch/x86/xen/xen-asm_64.S
index 48ac67e..c9c86a0 100644
--- a/arch/x86/xen/xen-asm_64.S
+++ b/arch/x86/xen/xen-asm_64.S
@@ -33,7 +33,7 @@ xen_pv_trap debug
xen_pv_trap xendebug
xen_pv_trap int3
xen_pv_trap xennmi
-xen_pv_trap overflow
+xen_pv_trap asm_exc_overflow
xen_pv_trap bounds
xen_pv_trap invalid_op
xen_pv_trap device_not_available