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Diffstat (limited to 'arch/s390/kernel/entry.S')
-rw-r--r--arch/s390/kernel/entry.S96
1 files changed, 84 insertions, 12 deletions
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 6a7d737d514c..6315037335ba 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -47,7 +47,7 @@ STACK_SIZE = 1 << STACK_SHIFT
STACK_INIT = STACK_SIZE - STACK_FRAME_OVERHEAD - __PT_SIZE
_TIF_WORK = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
- _TIF_UPROBE)
+ _TIF_UPROBE | _TIF_GUARDED_STORAGE | _TIF_PATCH_PENDING)
_TIF_TRACE = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
_TIF_SYSCALL_TRACEPOINT)
_CIF_WORK = (_CIF_MCCK_PENDING | _CIF_ASCE_PRIMARY | \
@@ -189,8 +189,6 @@ ENTRY(__switch_to)
stg %r3,__LC_CURRENT # store task struct of next
stg %r15,__LC_KERNEL_STACK # store end of kernel stack
lg %r15,__THREAD_ksp(%r1) # load kernel stack of next
- /* c4 is used in guest detection: arch/s390/kernel/perf_cpum_sf.c */
- lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
mvc __LC_CURRENT_PID(4,%r0),__TASK_pid(%r3) # store pid of next
lmg %r6,%r15,__SF_GPRS(%r15) # load gprs of next task
TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_LPP
@@ -233,12 +231,17 @@ ENTRY(sie64a)
lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
.Lsie_done:
# some program checks are suppressing. C code (e.g. do_protection_exception)
-# will rewind the PSW by the ILC, which is 4 bytes in case of SIE. Other
-# instructions between sie64a and .Lsie_done should not cause program
-# interrupts. So lets use a nop (47 00 00 00) as a landing pad.
+# will rewind the PSW by the ILC, which is often 4 bytes in case of SIE. There
+# are some corner cases (e.g. runtime instrumentation) where ILC is unpredictable.
+# Other instructions between sie64a and .Lsie_done should not cause program
+# interrupts. So lets use 3 nops as a landing pad for all possible rewinds.
# See also .Lcleanup_sie
-.Lrewind_pad:
- nop 0
+.Lrewind_pad6:
+ nopr 7
+.Lrewind_pad4:
+ nopr 7
+.Lrewind_pad2:
+ nopr 7
.globl sie_exit
sie_exit:
lg %r14,__SF_EMPTY+8(%r15) # load guest register save area
@@ -251,7 +254,9 @@ sie_exit:
stg %r14,__SF_EMPTY+16(%r15) # set exit reason code
j sie_exit
- EX_TABLE(.Lrewind_pad,.Lsie_fault)
+ EX_TABLE(.Lrewind_pad6,.Lsie_fault)
+ EX_TABLE(.Lrewind_pad4,.Lsie_fault)
+ EX_TABLE(.Lrewind_pad2,.Lsie_fault)
EX_TABLE(sie_exit,.Lsie_fault)
EXPORT_SYMBOL(sie64a)
EXPORT_SYMBOL(sie_exit)
@@ -314,6 +319,7 @@ ENTRY(system_call)
lg %r14,__LC_VDSO_PER_CPU
lmg %r0,%r10,__PT_R0(%r11)
mvc __LC_RETURN_PSW(16),__PT_PSW(%r11)
+.Lsysc_exit_timer:
stpt __LC_EXIT_TIMER
mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
lmg %r11,%r15,__PT_R11(%r11)
@@ -332,8 +338,15 @@ ENTRY(system_call)
TSTMSK __TI_flags(%r12),_TIF_UPROBE
jo .Lsysc_uprobe_notify
#endif
+ TSTMSK __TI_flags(%r12),_TIF_GUARDED_STORAGE
+ jo .Lsysc_guarded_storage
TSTMSK __PT_FLAGS(%r11),_PIF_PER_TRAP
jo .Lsysc_singlestep
+#ifdef CONFIG_LIVEPATCH
+ TSTMSK __TI_flags(%r12),_TIF_PATCH_PENDING
+ jo .Lsysc_patch_pending # handle live patching just before
+ # signals and possible syscall restart
+#endif
TSTMSK __TI_flags(%r12),_TIF_SIGPENDING
jo .Lsysc_sigpending
TSTMSK __TI_flags(%r12),_TIF_NOTIFY_RESUME
@@ -409,6 +422,23 @@ ENTRY(system_call)
#endif
#
+# _TIF_GUARDED_STORAGE is set, call guarded_storage_load
+#
+.Lsysc_guarded_storage:
+ lgr %r2,%r11 # pass pointer to pt_regs
+ larl %r14,.Lsysc_return
+ jg gs_load_bc_cb
+#
+# _TIF_PATCH_PENDING is set, call klp_update_patch_state
+#
+#ifdef CONFIG_LIVEPATCH
+.Lsysc_patch_pending:
+ lg %r2,__LC_CURRENT # pass pointer to task struct
+ larl %r14,.Lsysc_return
+ jg klp_update_patch_state
+#endif
+
+#
# _PIF_PER_TRAP is set, call do_per_trap
#
.Lsysc_singlestep:
@@ -601,6 +631,7 @@ ENTRY(io_int_handler)
lg %r14,__LC_VDSO_PER_CPU
lmg %r0,%r10,__PT_R0(%r11)
mvc __LC_RETURN_PSW(16),__PT_PSW(%r11)
+.Lio_exit_timer:
stpt __LC_EXIT_TIMER
mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
lmg %r11,%r15,__PT_R11(%r11)
@@ -659,10 +690,16 @@ ENTRY(io_int_handler)
jo .Lio_mcck_pending
TSTMSK __TI_flags(%r12),_TIF_NEED_RESCHED
jo .Lio_reschedule
+#ifdef CONFIG_LIVEPATCH
+ TSTMSK __TI_flags(%r12),_TIF_PATCH_PENDING
+ jo .Lio_patch_pending
+#endif
TSTMSK __TI_flags(%r12),_TIF_SIGPENDING
jo .Lio_sigpending
TSTMSK __TI_flags(%r12),_TIF_NOTIFY_RESUME
jo .Lio_notify_resume
+ TSTMSK __TI_flags(%r12),_TIF_GUARDED_STORAGE
+ jo .Lio_guarded_storage
TSTMSK __LC_CPU_FLAGS,_CIF_FPU
jo .Lio_vxrs
TSTMSK __LC_CPU_FLAGS,(_CIF_ASCE_PRIMARY|_CIF_ASCE_SECONDARY)
@@ -697,6 +734,18 @@ ENTRY(io_int_handler)
jg load_fpu_regs
#
+# _TIF_GUARDED_STORAGE is set, call guarded_storage_load
+#
+.Lio_guarded_storage:
+ # TRACE_IRQS_ON already done at .Lio_return
+ ssm __LC_SVC_NEW_PSW # reenable interrupts
+ lgr %r2,%r11 # pass pointer to pt_regs
+ brasl %r14,gs_load_bc_cb
+ ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
+ TRACE_IRQS_OFF
+ j .Lio_return
+
+#
# _TIF_NEED_RESCHED is set, call schedule
#
.Lio_reschedule:
@@ -708,6 +757,16 @@ ENTRY(io_int_handler)
j .Lio_return
#
+# _TIF_PATCH_PENDING is set, call klp_update_patch_state
+#
+#ifdef CONFIG_LIVEPATCH
+.Lio_patch_pending:
+ lg %r2,__LC_CURRENT # pass pointer to task struct
+ larl %r14,.Lio_return
+ jg klp_update_patch_state
+#endif
+
+#
# _TIF_SIGPENDING or is set, call do_signal
#
.Lio_sigpending:
@@ -1124,15 +1183,23 @@ cleanup_critical:
br %r14
.Lcleanup_sysc_restore:
+ # check if stpt has been executed
clg %r9,BASED(.Lcleanup_sysc_restore_insn)
+ jh 0f
+ mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
+ cghi %r11,__LC_SAVE_AREA_ASYNC
je 0f
+ mvc __LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
+0: clg %r9,BASED(.Lcleanup_sysc_restore_insn+8)
+ je 1f
lg %r9,24(%r11) # get saved pointer to pt_regs
mvc __LC_RETURN_PSW(16),__PT_PSW(%r9)
mvc 0(64,%r11),__PT_R8(%r9)
lmg %r0,%r7,__PT_R0(%r9)
-0: lmg %r8,%r9,__LC_RETURN_PSW
+1: lmg %r8,%r9,__LC_RETURN_PSW
br %r14
.Lcleanup_sysc_restore_insn:
+ .quad .Lsysc_exit_timer
.quad .Lsysc_done - 4
.Lcleanup_io_tif:
@@ -1140,15 +1207,20 @@ cleanup_critical:
br %r14
.Lcleanup_io_restore:
+ # check if stpt has been executed
clg %r9,BASED(.Lcleanup_io_restore_insn)
- je 0f
+ jh 0f
+ mvc __LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
+0: clg %r9,BASED(.Lcleanup_io_restore_insn+8)
+ je 1f
lg %r9,24(%r11) # get saved r11 pointer to pt_regs
mvc __LC_RETURN_PSW(16),__PT_PSW(%r9)
mvc 0(64,%r11),__PT_R8(%r9)
lmg %r0,%r7,__PT_R0(%r9)
-0: lmg %r8,%r9,__LC_RETURN_PSW
+1: lmg %r8,%r9,__LC_RETURN_PSW
br %r14
.Lcleanup_io_restore_insn:
+ .quad .Lio_exit_timer
.quad .Lio_done - 4
.Lcleanup_idle: