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authorIngo Molnar <mingo@elte.hu>2006-07-03 03:24:45 -0400
committerLinus Torvalds <torvalds@g5.osdl.org>2006-07-03 18:27:03 -0400
commit2601e64d262ee5ed4d4a5737345803800d9c4db3 (patch)
tree67f852752af3c54f745b93f7016cdd7c5ffb1a14 /arch/x86_64
parentc8558fcdecb1f920df8050be4f2d5f499060030e (diff)
[PATCH] lockdep: irqtrace subsystem, x86_64 support
Add irqflags-tracing support to x86_64. [akpm@osdl.org: build fix] Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/x86_64')
-rw-r--r--arch/x86_64/Kconfig.debug4
-rw-r--r--arch/x86_64/ia32/ia32entry.S19
-rw-r--r--arch/x86_64/kernel/entry.S188
-rw-r--r--arch/x86_64/kernel/irq.c4
4 files changed, 161 insertions, 54 deletions
diff --git a/arch/x86_64/Kconfig.debug b/arch/x86_64/Kconfig.debug
index 1d92ab56c0f9..775d211a5cf9 100644
--- a/arch/x86_64/Kconfig.debug
+++ b/arch/x86_64/Kconfig.debug
@@ -1,5 +1,9 @@
1menu "Kernel hacking" 1menu "Kernel hacking"
2 2
3config TRACE_IRQFLAGS_SUPPORT
4 bool
5 default y
6
3source "lib/Kconfig.debug" 7source "lib/Kconfig.debug"
4 8
5config DEBUG_RODATA 9config DEBUG_RODATA
diff --git a/arch/x86_64/ia32/ia32entry.S b/arch/x86_64/ia32/ia32entry.S
index c536fa98ea37..9b5bb413a6e9 100644
--- a/arch/x86_64/ia32/ia32entry.S
+++ b/arch/x86_64/ia32/ia32entry.S
@@ -13,6 +13,7 @@
13#include <asm/thread_info.h> 13#include <asm/thread_info.h>
14#include <asm/segment.h> 14#include <asm/segment.h>
15#include <asm/vsyscall32.h> 15#include <asm/vsyscall32.h>
16#include <asm/irqflags.h>
16#include <linux/linkage.h> 17#include <linux/linkage.h>
17 18
18#define IA32_NR_syscalls ((ia32_syscall_end - ia32_sys_call_table)/8) 19#define IA32_NR_syscalls ((ia32_syscall_end - ia32_sys_call_table)/8)
@@ -75,6 +76,10 @@ ENTRY(ia32_sysenter_target)
75 swapgs 76 swapgs
76 movq %gs:pda_kernelstack, %rsp 77 movq %gs:pda_kernelstack, %rsp
77 addq $(PDA_STACKOFFSET),%rsp 78 addq $(PDA_STACKOFFSET),%rsp
79 /*
80 * No need to follow this irqs on/off section: the syscall
81 * disabled irqs, here we enable it straight after entry:
82 */
78 sti 83 sti
79 movl %ebp,%ebp /* zero extension */ 84 movl %ebp,%ebp /* zero extension */
80 pushq $__USER32_DS 85 pushq $__USER32_DS
@@ -118,6 +123,7 @@ sysenter_do_call:
118 movq %rax,RAX-ARGOFFSET(%rsp) 123 movq %rax,RAX-ARGOFFSET(%rsp)
119 GET_THREAD_INFO(%r10) 124 GET_THREAD_INFO(%r10)
120 cli 125 cli
126 TRACE_IRQS_OFF
121 testl $_TIF_ALLWORK_MASK,threadinfo_flags(%r10) 127 testl $_TIF_ALLWORK_MASK,threadinfo_flags(%r10)
122 jnz int_ret_from_sys_call 128 jnz int_ret_from_sys_call
123 andl $~TS_COMPAT,threadinfo_status(%r10) 129 andl $~TS_COMPAT,threadinfo_status(%r10)
@@ -132,6 +138,7 @@ sysenter_do_call:
132 CFI_REGISTER rsp,rcx 138 CFI_REGISTER rsp,rcx
133 movl $VSYSCALL32_SYSEXIT,%edx /* User %eip */ 139 movl $VSYSCALL32_SYSEXIT,%edx /* User %eip */
134 CFI_REGISTER rip,rdx 140 CFI_REGISTER rip,rdx
141 TRACE_IRQS_ON
135 swapgs 142 swapgs
136 sti /* sti only takes effect after the next instruction */ 143 sti /* sti only takes effect after the next instruction */
137 /* sysexit */ 144 /* sysexit */
@@ -186,6 +193,10 @@ ENTRY(ia32_cstar_target)
186 movl %esp,%r8d 193 movl %esp,%r8d
187 CFI_REGISTER rsp,r8 194 CFI_REGISTER rsp,r8
188 movq %gs:pda_kernelstack,%rsp 195 movq %gs:pda_kernelstack,%rsp
196 /*
197 * No need to follow this irqs on/off section: the syscall
198 * disabled irqs and here we enable it straight after entry:
199 */
189 sti 200 sti
190 SAVE_ARGS 8,1,1 201 SAVE_ARGS 8,1,1
191 movl %eax,%eax /* zero extension */ 202 movl %eax,%eax /* zero extension */
@@ -220,6 +231,7 @@ cstar_do_call:
220 movq %rax,RAX-ARGOFFSET(%rsp) 231 movq %rax,RAX-ARGOFFSET(%rsp)
221 GET_THREAD_INFO(%r10) 232 GET_THREAD_INFO(%r10)
222 cli 233 cli
234 TRACE_IRQS_OFF
223 testl $_TIF_ALLWORK_MASK,threadinfo_flags(%r10) 235 testl $_TIF_ALLWORK_MASK,threadinfo_flags(%r10)
224 jnz int_ret_from_sys_call 236 jnz int_ret_from_sys_call
225 andl $~TS_COMPAT,threadinfo_status(%r10) 237 andl $~TS_COMPAT,threadinfo_status(%r10)
@@ -228,6 +240,7 @@ cstar_do_call:
228 CFI_REGISTER rip,rcx 240 CFI_REGISTER rip,rcx
229 movl EFLAGS-ARGOFFSET(%rsp),%r11d 241 movl EFLAGS-ARGOFFSET(%rsp),%r11d
230 /*CFI_REGISTER rflags,r11*/ 242 /*CFI_REGISTER rflags,r11*/
243 TRACE_IRQS_ON
231 movl RSP-ARGOFFSET(%rsp),%esp 244 movl RSP-ARGOFFSET(%rsp),%esp
232 CFI_RESTORE rsp 245 CFI_RESTORE rsp
233 swapgs 246 swapgs
@@ -286,7 +299,11 @@ ENTRY(ia32_syscall)
286 /*CFI_REL_OFFSET rflags,EFLAGS-RIP*/ 299 /*CFI_REL_OFFSET rflags,EFLAGS-RIP*/
287 /*CFI_REL_OFFSET cs,CS-RIP*/ 300 /*CFI_REL_OFFSET cs,CS-RIP*/
288 CFI_REL_OFFSET rip,RIP-RIP 301 CFI_REL_OFFSET rip,RIP-RIP
289 swapgs 302 swapgs
303 /*
304 * No need to follow this irqs on/off section: the syscall
305 * disabled irqs and here we enable it straight after entry:
306 */
290 sti 307 sti
291 movl %eax,%eax 308 movl %eax,%eax
292 pushq %rax 309 pushq %rax
diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S
index ed92c2983606..d464dded68c0 100644
--- a/arch/x86_64/kernel/entry.S
+++ b/arch/x86_64/kernel/entry.S
@@ -41,13 +41,24 @@
41#include <asm/thread_info.h> 41#include <asm/thread_info.h>
42#include <asm/hw_irq.h> 42#include <asm/hw_irq.h>
43#include <asm/page.h> 43#include <asm/page.h>
44#include <asm/irqflags.h>
44 45
45 .code64 46 .code64
46 47
47#ifndef CONFIG_PREEMPT 48#ifndef CONFIG_PREEMPT
48#define retint_kernel retint_restore_args 49#define retint_kernel retint_restore_args
49#endif 50#endif
50 51
52
53.macro TRACE_IRQS_IRETQ offset=ARGOFFSET
54#ifdef CONFIG_TRACE_IRQFLAGS
55 bt $9,EFLAGS-\offset(%rsp) /* interrupts off? */
56 jnc 1f
57 TRACE_IRQS_ON
581:
59#endif
60.endm
61
51/* 62/*
52 * C code is not supposed to know about undefined top of stack. Every time 63 * C code is not supposed to know about undefined top of stack. Every time
53 * a C function with an pt_regs argument is called from the SYSCALL based 64 * a C function with an pt_regs argument is called from the SYSCALL based
@@ -194,6 +205,10 @@ ENTRY(system_call)
194 swapgs 205 swapgs
195 movq %rsp,%gs:pda_oldrsp 206 movq %rsp,%gs:pda_oldrsp
196 movq %gs:pda_kernelstack,%rsp 207 movq %gs:pda_kernelstack,%rsp
208 /*
209 * No need to follow this irqs off/on section - it's straight
210 * and short:
211 */
197 sti 212 sti
198 SAVE_ARGS 8,1 213 SAVE_ARGS 8,1
199 movq %rax,ORIG_RAX-ARGOFFSET(%rsp) 214 movq %rax,ORIG_RAX-ARGOFFSET(%rsp)
@@ -219,10 +234,15 @@ ret_from_sys_call:
219sysret_check: 234sysret_check:
220 GET_THREAD_INFO(%rcx) 235 GET_THREAD_INFO(%rcx)
221 cli 236 cli
237 TRACE_IRQS_OFF
222 movl threadinfo_flags(%rcx),%edx 238 movl threadinfo_flags(%rcx),%edx
223 andl %edi,%edx 239 andl %edi,%edx
224 CFI_REMEMBER_STATE 240 CFI_REMEMBER_STATE
225 jnz sysret_careful 241 jnz sysret_careful
242 /*
243 * sysretq will re-enable interrupts:
244 */
245 TRACE_IRQS_ON
226 movq RIP-ARGOFFSET(%rsp),%rcx 246 movq RIP-ARGOFFSET(%rsp),%rcx
227 CFI_REGISTER rip,rcx 247 CFI_REGISTER rip,rcx
228 RESTORE_ARGS 0,-ARG_SKIP,1 248 RESTORE_ARGS 0,-ARG_SKIP,1
@@ -237,6 +257,7 @@ sysret_careful:
237 CFI_RESTORE_STATE 257 CFI_RESTORE_STATE
238 bt $TIF_NEED_RESCHED,%edx 258 bt $TIF_NEED_RESCHED,%edx
239 jnc sysret_signal 259 jnc sysret_signal
260 TRACE_IRQS_ON
240 sti 261 sti
241 pushq %rdi 262 pushq %rdi
242 CFI_ADJUST_CFA_OFFSET 8 263 CFI_ADJUST_CFA_OFFSET 8
@@ -247,6 +268,7 @@ sysret_careful:
247 268
248 /* Handle a signal */ 269 /* Handle a signal */
249sysret_signal: 270sysret_signal:
271 TRACE_IRQS_ON
250 sti 272 sti
251 testl $(_TIF_SIGPENDING|_TIF_NOTIFY_RESUME|_TIF_SINGLESTEP),%edx 273 testl $(_TIF_SIGPENDING|_TIF_NOTIFY_RESUME|_TIF_SINGLESTEP),%edx
252 jz 1f 274 jz 1f
@@ -261,6 +283,7 @@ sysret_signal:
261 /* Use IRET because user could have changed frame. This 283 /* Use IRET because user could have changed frame. This
262 works because ptregscall_common has called FIXUP_TOP_OF_STACK. */ 284 works because ptregscall_common has called FIXUP_TOP_OF_STACK. */
263 cli 285 cli
286 TRACE_IRQS_OFF
264 jmp int_with_check 287 jmp int_with_check
265 288
266badsys: 289badsys:
@@ -309,6 +332,7 @@ ENTRY(int_ret_from_sys_call)
309 CFI_REL_OFFSET r10,R10-ARGOFFSET 332 CFI_REL_OFFSET r10,R10-ARGOFFSET
310 CFI_REL_OFFSET r11,R11-ARGOFFSET 333 CFI_REL_OFFSET r11,R11-ARGOFFSET
311 cli 334 cli
335 TRACE_IRQS_OFF
312 testl $3,CS-ARGOFFSET(%rsp) 336 testl $3,CS-ARGOFFSET(%rsp)
313 je retint_restore_args 337 je retint_restore_args
314 movl $_TIF_ALLWORK_MASK,%edi 338 movl $_TIF_ALLWORK_MASK,%edi
@@ -327,6 +351,7 @@ int_with_check:
327int_careful: 351int_careful:
328 bt $TIF_NEED_RESCHED,%edx 352 bt $TIF_NEED_RESCHED,%edx
329 jnc int_very_careful 353 jnc int_very_careful
354 TRACE_IRQS_ON
330 sti 355 sti
331 pushq %rdi 356 pushq %rdi
332 CFI_ADJUST_CFA_OFFSET 8 357 CFI_ADJUST_CFA_OFFSET 8
@@ -334,10 +359,12 @@ int_careful:
334 popq %rdi 359 popq %rdi
335 CFI_ADJUST_CFA_OFFSET -8 360 CFI_ADJUST_CFA_OFFSET -8
336 cli 361 cli
362 TRACE_IRQS_OFF
337 jmp int_with_check 363 jmp int_with_check
338 364
339 /* handle signals and tracing -- both require a full stack frame */ 365 /* handle signals and tracing -- both require a full stack frame */
340int_very_careful: 366int_very_careful:
367 TRACE_IRQS_ON
341 sti 368 sti
342 SAVE_REST 369 SAVE_REST
343 /* Check for syscall exit trace */ 370 /* Check for syscall exit trace */
@@ -351,6 +378,7 @@ int_very_careful:
351 CFI_ADJUST_CFA_OFFSET -8 378 CFI_ADJUST_CFA_OFFSET -8
352 andl $~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP),%edi 379 andl $~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP),%edi
353 cli 380 cli
381 TRACE_IRQS_OFF
354 jmp int_restore_rest 382 jmp int_restore_rest
355 383
356int_signal: 384int_signal:
@@ -363,6 +391,7 @@ int_signal:
363int_restore_rest: 391int_restore_rest:
364 RESTORE_REST 392 RESTORE_REST
365 cli 393 cli
394 TRACE_IRQS_OFF
366 jmp int_with_check 395 jmp int_with_check
367 CFI_ENDPROC 396 CFI_ENDPROC
368END(int_ret_from_sys_call) 397END(int_ret_from_sys_call)
@@ -484,6 +513,10 @@ END(stub_rt_sigreturn)
484 swapgs 513 swapgs
4851: incl %gs:pda_irqcount # RED-PEN should check preempt count 5141: incl %gs:pda_irqcount # RED-PEN should check preempt count
486 cmoveq %gs:pda_irqstackptr,%rsp 515 cmoveq %gs:pda_irqstackptr,%rsp
516 /*
517 * We entered an interrupt context - irqs are off:
518 */
519 TRACE_IRQS_OFF
487 call \func 520 call \func
488 .endm 521 .endm
489 522
@@ -493,6 +526,7 @@ ENTRY(common_interrupt)
493 /* 0(%rsp): oldrsp-ARGOFFSET */ 526 /* 0(%rsp): oldrsp-ARGOFFSET */
494ret_from_intr: 527ret_from_intr:
495 cli 528 cli
529 TRACE_IRQS_OFF
496 decl %gs:pda_irqcount 530 decl %gs:pda_irqcount
497 leaveq 531 leaveq
498 CFI_DEF_CFA_REGISTER rsp 532 CFI_DEF_CFA_REGISTER rsp
@@ -515,9 +549,21 @@ retint_check:
515 CFI_REMEMBER_STATE 549 CFI_REMEMBER_STATE
516 jnz retint_careful 550 jnz retint_careful
517retint_swapgs: 551retint_swapgs:
552 /*
553 * The iretq could re-enable interrupts:
554 */
555 cli
556 TRACE_IRQS_IRETQ
518 swapgs 557 swapgs
558 jmp restore_args
559
519retint_restore_args: 560retint_restore_args:
520 cli 561 cli
562 /*
563 * The iretq could re-enable interrupts:
564 */
565 TRACE_IRQS_IRETQ
566restore_args:
521 RESTORE_ARGS 0,8,0 567 RESTORE_ARGS 0,8,0
522iret_label: 568iret_label:
523 iretq 569 iretq
@@ -530,6 +576,7 @@ iret_label:
530 /* running with kernel gs */ 576 /* running with kernel gs */
531bad_iret: 577bad_iret:
532 movq $11,%rdi /* SIGSEGV */ 578 movq $11,%rdi /* SIGSEGV */
579 TRACE_IRQS_ON
533 sti 580 sti
534 jmp do_exit 581 jmp do_exit
535 .previous 582 .previous
@@ -539,6 +586,7 @@ retint_careful:
539 CFI_RESTORE_STATE 586 CFI_RESTORE_STATE
540 bt $TIF_NEED_RESCHED,%edx 587 bt $TIF_NEED_RESCHED,%edx
541 jnc retint_signal 588 jnc retint_signal
589 TRACE_IRQS_ON
542 sti 590 sti
543 pushq %rdi 591 pushq %rdi
544 CFI_ADJUST_CFA_OFFSET 8 592 CFI_ADJUST_CFA_OFFSET 8
@@ -547,11 +595,13 @@ retint_careful:
547 CFI_ADJUST_CFA_OFFSET -8 595 CFI_ADJUST_CFA_OFFSET -8
548 GET_THREAD_INFO(%rcx) 596 GET_THREAD_INFO(%rcx)
549 cli 597 cli
598 TRACE_IRQS_OFF
550 jmp retint_check 599 jmp retint_check
551 600
552retint_signal: 601retint_signal:
553 testl $(_TIF_SIGPENDING|_TIF_NOTIFY_RESUME|_TIF_SINGLESTEP),%edx 602 testl $(_TIF_SIGPENDING|_TIF_NOTIFY_RESUME|_TIF_SINGLESTEP),%edx
554 jz retint_swapgs 603 jz retint_swapgs
604 TRACE_IRQS_ON
555 sti 605 sti
556 SAVE_REST 606 SAVE_REST
557 movq $-1,ORIG_RAX(%rsp) 607 movq $-1,ORIG_RAX(%rsp)
@@ -560,6 +610,7 @@ retint_signal:
560 call do_notify_resume 610 call do_notify_resume
561 RESTORE_REST 611 RESTORE_REST
562 cli 612 cli
613 TRACE_IRQS_OFF
563 movl $_TIF_NEED_RESCHED,%edi 614 movl $_TIF_NEED_RESCHED,%edi
564 GET_THREAD_INFO(%rcx) 615 GET_THREAD_INFO(%rcx)
565 jmp retint_check 616 jmp retint_check
@@ -666,7 +717,7 @@ END(spurious_interrupt)
666 717
667 /* error code is on the stack already */ 718 /* error code is on the stack already */
668 /* handle NMI like exceptions that can happen everywhere */ 719 /* handle NMI like exceptions that can happen everywhere */
669 .macro paranoidentry sym, ist=0 720 .macro paranoidentry sym, ist=0, irqtrace=1
670 SAVE_ALL 721 SAVE_ALL
671 cld 722 cld
672 movl $1,%ebx 723 movl $1,%ebx
@@ -691,8 +742,73 @@ END(spurious_interrupt)
691 addq $EXCEPTION_STKSZ, per_cpu__init_tss + TSS_ist + (\ist - 1) * 8(%rbp) 742 addq $EXCEPTION_STKSZ, per_cpu__init_tss + TSS_ist + (\ist - 1) * 8(%rbp)
692 .endif 743 .endif
693 cli 744 cli
745 .if \irqtrace
746 TRACE_IRQS_OFF
747 .endif
694 .endm 748 .endm
695 749
750 /*
751 * "Paranoid" exit path from exception stack.
752 * Paranoid because this is used by NMIs and cannot take
753 * any kernel state for granted.
754 * We don't do kernel preemption checks here, because only
755 * NMI should be common and it does not enable IRQs and
756 * cannot get reschedule ticks.
757 *
758 * "trace" is 0 for the NMI handler only, because irq-tracing
759 * is fundamentally NMI-unsafe. (we cannot change the soft and
760 * hard flags at once, atomically)
761 */
762 .macro paranoidexit trace=1
763 /* ebx: no swapgs flag */
764paranoid_exit\trace:
765 testl %ebx,%ebx /* swapgs needed? */
766 jnz paranoid_restore\trace
767 testl $3,CS(%rsp)
768 jnz paranoid_userspace\trace
769paranoid_swapgs\trace:
770 TRACE_IRQS_IRETQ 0
771 swapgs
772paranoid_restore\trace:
773 RESTORE_ALL 8
774 iretq
775paranoid_userspace\trace:
776 GET_THREAD_INFO(%rcx)
777 movl threadinfo_flags(%rcx),%ebx
778 andl $_TIF_WORK_MASK,%ebx
779 jz paranoid_swapgs\trace
780 movq %rsp,%rdi /* &pt_regs */
781 call sync_regs
782 movq %rax,%rsp /* switch stack for scheduling */
783 testl $_TIF_NEED_RESCHED,%ebx
784 jnz paranoid_schedule\trace
785 movl %ebx,%edx /* arg3: thread flags */
786 .if \trace
787 TRACE_IRQS_ON
788 .endif
789 sti
790 xorl %esi,%esi /* arg2: oldset */
791 movq %rsp,%rdi /* arg1: &pt_regs */
792 call do_notify_resume
793 cli
794 .if \trace
795 TRACE_IRQS_OFF
796 .endif
797 jmp paranoid_userspace\trace
798paranoid_schedule\trace:
799 .if \trace
800 TRACE_IRQS_ON
801 .endif
802 sti
803 call schedule
804 cli
805 .if \trace
806 TRACE_IRQS_OFF
807 .endif
808 jmp paranoid_userspace\trace
809 CFI_ENDPROC
810 .endm
811
696/* 812/*
697 * Exception entry point. This expects an error code/orig_rax on the stack 813 * Exception entry point. This expects an error code/orig_rax on the stack
698 * and the exception handler in %rax. 814 * and the exception handler in %rax.
@@ -748,6 +864,7 @@ error_exit:
748 movl %ebx,%eax 864 movl %ebx,%eax
749 RESTORE_REST 865 RESTORE_REST
750 cli 866 cli
867 TRACE_IRQS_OFF
751 GET_THREAD_INFO(%rcx) 868 GET_THREAD_INFO(%rcx)
752 testl %eax,%eax 869 testl %eax,%eax
753 jne retint_kernel 870 jne retint_kernel
@@ -755,6 +872,10 @@ error_exit:
755 movl $_TIF_WORK_MASK,%edi 872 movl $_TIF_WORK_MASK,%edi
756 andl %edi,%edx 873 andl %edi,%edx
757 jnz retint_careful 874 jnz retint_careful
875 /*
876 * The iret might restore flags:
877 */
878 TRACE_IRQS_IRETQ
758 swapgs 879 swapgs
759 RESTORE_ARGS 0,8,0 880 RESTORE_ARGS 0,8,0
760 jmp iret_label 881 jmp iret_label
@@ -916,8 +1037,7 @@ KPROBE_ENTRY(debug)
916 pushq $0 1037 pushq $0
917 CFI_ADJUST_CFA_OFFSET 8 1038 CFI_ADJUST_CFA_OFFSET 8
918 paranoidentry do_debug, DEBUG_STACK 1039 paranoidentry do_debug, DEBUG_STACK
919 jmp paranoid_exit 1040 paranoidexit
920 CFI_ENDPROC
921END(debug) 1041END(debug)
922 .previous .text 1042 .previous .text
923 1043
@@ -926,49 +1046,13 @@ KPROBE_ENTRY(nmi)
926 INTR_FRAME 1046 INTR_FRAME
927 pushq $-1 1047 pushq $-1
928 CFI_ADJUST_CFA_OFFSET 8 1048 CFI_ADJUST_CFA_OFFSET 8
929 paranoidentry do_nmi 1049 paranoidentry do_nmi, 0, 0
930 /* 1050#ifdef CONFIG_TRACE_IRQFLAGS
931 * "Paranoid" exit path from exception stack. 1051 paranoidexit 0
932 * Paranoid because this is used by NMIs and cannot take 1052#else
933 * any kernel state for granted. 1053 jmp paranoid_exit1
934 * We don't do kernel preemption checks here, because only 1054 CFI_ENDPROC
935 * NMI should be common and it does not enable IRQs and 1055#endif
936 * cannot get reschedule ticks.
937 */
938 /* ebx: no swapgs flag */
939paranoid_exit:
940 testl %ebx,%ebx /* swapgs needed? */
941 jnz paranoid_restore
942 testl $3,CS(%rsp)
943 jnz paranoid_userspace
944paranoid_swapgs:
945 swapgs
946paranoid_restore:
947 RESTORE_ALL 8
948 iretq
949paranoid_userspace:
950 GET_THREAD_INFO(%rcx)
951 movl threadinfo_flags(%rcx),%ebx
952 andl $_TIF_WORK_MASK,%ebx
953 jz paranoid_swapgs
954 movq %rsp,%rdi /* &pt_regs */
955 call sync_regs
956 movq %rax,%rsp /* switch stack for scheduling */
957 testl $_TIF_NEED_RESCHED,%ebx
958 jnz paranoid_schedule
959 movl %ebx,%edx /* arg3: thread flags */
960 sti
961 xorl %esi,%esi /* arg2: oldset */
962 movq %rsp,%rdi /* arg1: &pt_regs */
963 call do_notify_resume
964 cli
965 jmp paranoid_userspace
966paranoid_schedule:
967 sti
968 call schedule
969 cli
970 jmp paranoid_userspace
971 CFI_ENDPROC
972END(nmi) 1056END(nmi)
973 .previous .text 1057 .previous .text
974 1058
@@ -977,7 +1061,7 @@ KPROBE_ENTRY(int3)
977 pushq $0 1061 pushq $0
978 CFI_ADJUST_CFA_OFFSET 8 1062 CFI_ADJUST_CFA_OFFSET 8
979 paranoidentry do_int3, DEBUG_STACK 1063 paranoidentry do_int3, DEBUG_STACK
980 jmp paranoid_exit 1064 jmp paranoid_exit1
981 CFI_ENDPROC 1065 CFI_ENDPROC
982END(int3) 1066END(int3)
983 .previous .text 1067 .previous .text
@@ -1006,7 +1090,7 @@ END(reserved)
1006ENTRY(double_fault) 1090ENTRY(double_fault)
1007 XCPT_FRAME 1091 XCPT_FRAME
1008 paranoidentry do_double_fault 1092 paranoidentry do_double_fault
1009 jmp paranoid_exit 1093 jmp paranoid_exit1
1010 CFI_ENDPROC 1094 CFI_ENDPROC
1011END(double_fault) 1095END(double_fault)
1012 1096
@@ -1022,7 +1106,7 @@ END(segment_not_present)
1022ENTRY(stack_segment) 1106ENTRY(stack_segment)
1023 XCPT_FRAME 1107 XCPT_FRAME
1024 paranoidentry do_stack_segment 1108 paranoidentry do_stack_segment
1025 jmp paranoid_exit 1109 jmp paranoid_exit1
1026 CFI_ENDPROC 1110 CFI_ENDPROC
1027END(stack_segment) 1111END(stack_segment)
1028 1112
@@ -1050,7 +1134,7 @@ ENTRY(machine_check)
1050 pushq $0 1134 pushq $0
1051 CFI_ADJUST_CFA_OFFSET 8 1135 CFI_ADJUST_CFA_OFFSET 8
1052 paranoidentry do_machine_check 1136 paranoidentry do_machine_check
1053 jmp paranoid_exit 1137 jmp paranoid_exit1
1054 CFI_ENDPROC 1138 CFI_ENDPROC
1055END(machine_check) 1139END(machine_check)
1056#endif 1140#endif
diff --git a/arch/x86_64/kernel/irq.c b/arch/x86_64/kernel/irq.c
index a1f1df5f7bfc..5221a53e90c1 100644
--- a/arch/x86_64/kernel/irq.c
+++ b/arch/x86_64/kernel/irq.c
@@ -177,8 +177,10 @@ asmlinkage void do_softirq(void)
177 local_irq_save(flags); 177 local_irq_save(flags);
178 pending = local_softirq_pending(); 178 pending = local_softirq_pending();
179 /* Switch to interrupt stack */ 179 /* Switch to interrupt stack */
180 if (pending) 180 if (pending) {
181 call_softirq(); 181 call_softirq();
182 WARN_ON_ONCE(softirq_count());
183 }
182 local_irq_restore(flags); 184 local_irq_restore(flags);
183} 185}
184EXPORT_SYMBOL(do_softirq); 186EXPORT_SYMBOL(do_softirq);