x86/entry: Convert Device not available exception to IDTENTRY

Convert #NM 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
  - 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: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134905.056243863@linutronix.de

diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index 95a96020f9e48c66204c28d74a3047f5a8cf54a9..7d7f2836c0716adccd5478c7f6438dcd043301ff 100644 (file)
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -1311,13 +1311,6 @@ SYM_CODE_START(simd_coprocessor_error)
        jmp     common_exception
 SYM_CODE_END(simd_coprocessor_error)
 
-SYM_CODE_START(device_not_available)
-       ASM_CLAC
-       pushl   $0
-       pushl   $do_device_not_available
-       jmp     common_exception
-SYM_CODE_END(device_not_available)
-
 #ifdef CONFIG_PARAVIRT
 SYM_CODE_START(native_iret)
        iret

diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index ebd5f9fa4f5c82eca2f1bf187d7dad5b5a893087..d7cf00026d33175c8ad426387bf9c98ecfbc9545 100644 (file)
--- 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_NM             device_not_available    do_device_not_available         has_error_code=0
 idtentry       X86_TRAP_OLD_MF         coprocessor_segment_overrun     do_coprocessor_segment_overrun  has_error_code=0
 idtentry       X86_TRAP_TS             invalid_TSS             do_invalid_TSS                  has_error_code=1
 idtentry       X86_TRAP_NP             segment_not_present     do_segment_not_present          has_error_code=1

diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h
index f34630f098646ae5b3aa03e6e5f1420c056d0987..fd6f996ce5845c046b19bfea905236d1e0cc65a0 100644 (file)
--- a/arch/x86/include/asm/idtentry.h
+++ b/arch/x86/include/asm/idtentry.h
@@ -81,5 +81,6 @@ DECLARE_IDTENTRY(X86_TRAP_DE,         exc_divide_error);
 DECLARE_IDTENTRY(X86_TRAP_OF,          exc_overflow);
 DECLARE_IDTENTRY(X86_TRAP_BR,          exc_bounds);
 DECLARE_IDTENTRY(X86_TRAP_UD,          exc_invalid_op);
+DECLARE_IDTENTRY(X86_TRAP_NM,          exc_device_not_available);
 
 #endif

diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h
index 71a4a7e6ba8985b3d06f86576935e740dbd84a26..e5f2c90c0e8bcb453b41e12a560c06a9bc9749a6 100644 (file)
--- 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 device_not_available(void);
 #ifdef CONFIG_X86_64
 asmlinkage void double_fault(void);
 #endif
@@ -37,7 +36,6 @@ asmlinkage void simd_coprocessor_error(void);
 asmlinkage void xen_xennmi(void);
 asmlinkage void xen_xendebug(void);
 asmlinkage void xen_int3(void);
-asmlinkage void xen_device_not_available(void);
 asmlinkage void xen_double_fault(void);
 asmlinkage void xen_coprocessor_segment_overrun(void);
 asmlinkage void xen_invalid_TSS(void);
@@ -57,7 +55,6 @@ 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_device_not_available(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_coprocessor_segment_overrun(struct pt_regs *regs, long error_code);
 dotraplinkage void do_invalid_TSS(struct pt_regs *regs, long error_code);

diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index 8b48f54aeff61b618c3ea756ef49941b0a7a9513..cdc2d8bbd338e3d7243d382fca56c8042119b53a 100644 (file)
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -77,7 +77,7 @@ static const __initconst struct idt_data def_idts[] = {
        INTG(X86_TRAP_NMI,              nmi),
        INTG(X86_TRAP_BR,               asm_exc_bounds),
        INTG(X86_TRAP_UD,               asm_exc_invalid_op),
-       INTG(X86_TRAP_NM,               device_not_available),
+       INTG(X86_TRAP_NM,               asm_exc_device_not_available),
        INTG(X86_TRAP_OLD_MF,           coprocessor_segment_overrun),
        INTG(X86_TRAP_TS,               invalid_TSS),
        INTG(X86_TRAP_NP,               segment_not_present),

diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 71ac43dc036a1700827c3c724b8a8530761a6253..b8af5eb6a92911acc661f094e5631785bee14c59 100644 (file)
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -882,13 +882,10 @@ do_spurious_interrupt_bug(struct pt_regs *regs, long error_code)
         */
 }
 
-dotraplinkage void
-do_device_not_available(struct pt_regs *regs, long error_code)
+DEFINE_IDTENTRY(exc_device_not_available)
 {
        unsigned long cr0 = read_cr0();
 
-       RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
-
 #ifdef CONFIG_MATH_EMULATION
        if (!boot_cpu_has(X86_FEATURE_FPU) && (cr0 & X86_CR0_EM)) {
                struct math_emu_info info = { };
@@ -913,10 +910,9 @@ do_device_not_available(struct pt_regs *regs, long error_code)
                 * to kill the task than getting stuck in a never-ending
                 * loop of #NM faults.
                 */
-               die("unexpected #NM exception", regs, error_code);
+               die("unexpected #NM exception", regs, 0);
        }
 }
-NOKPROBE_SYMBOL(do_device_not_available);
 
 #ifdef CONFIG_X86_32
 dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code)

diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 5a0e60986e19641d31ec41e5efb5ae7aca627fa3..94e2f918403ec9fd6f02ee778fd3d7480989450b 100644 (file)
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -625,7 +625,7 @@ static struct trap_array_entry trap_array[] = {
        TRAP_ENTRY(exc_divide_error,                    false ),
        TRAP_ENTRY(exc_bounds,                          false ),
        TRAP_ENTRY(exc_invalid_op,                      false ),
-       { device_not_available,        xen_device_not_available,        false },
+       TRAP_ENTRY(exc_device_not_available,            false ),
        { coprocessor_segment_overrun, xen_coprocessor_segment_overrun, false },
        { invalid_TSS,                 xen_invalid_TSS,                 false },
        { segment_not_present,         xen_segment_not_present,         false },

diff --git a/arch/x86/xen/xen-asm_64.S b/arch/x86/xen/xen-asm_64.S
index 999f09e8bb09e60d45b909e96a7455cd47bcec16..5215e5724cfb619fa9ee826f430a8e810a266720 100644 (file)
--- a/arch/x86/xen/xen-asm_64.S
+++ b/arch/x86/xen/xen-asm_64.S
@@ -36,7 +36,7 @@ xen_pv_trap xennmi
 xen_pv_trap asm_exc_overflow
 xen_pv_trap asm_exc_bounds
 xen_pv_trap asm_exc_invalid_op
-xen_pv_trap device_not_available
+xen_pv_trap asm_exc_device_not_available
 xen_pv_trap double_fault
 xen_pv_trap coprocessor_segment_overrun
 xen_pv_trap invalid_TSS