diff options
Diffstat (limited to 'arch/s390/kernel/entry.S')
| -rw-r--r-- | arch/s390/kernel/entry.S | 1357 |
1 files changed, 519 insertions, 838 deletions
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S index be7a408be7a1..b7f1553d9ee5 100644 --- a/arch/s390/kernel/entry.S +++ b/arch/s390/kernel/entry.S @@ -1,3 +1,4 @@ +/* SPDX-License-Identifier: GPL-2.0 */ /* * S390 low-level entry points. * @@ -5,12 +6,16 @@ * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), * Hartmut Penner (hp@de.ibm.com), * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com), - * Heiko Carstens <heiko.carstens@de.ibm.com> */ +#include <linux/export.h> #include <linux/init.h> #include <linux/linkage.h> +#include <asm/asm-extable.h> +#include <asm/alternative.h> +#include <asm/processor.h> #include <asm/cache.h> +#include <asm/dwarf.h> #include <asm/errno.h> #include <asm/ptrace.h> #include <asm/thread_info.h> @@ -18,916 +23,592 @@ #include <asm/unistd.h> #include <asm/page.h> #include <asm/sigp.h> +#include <asm/irq.h> +#include <asm/fpu-insn.h> +#include <asm/setup.h> +#include <asm/nmi.h> +#include <asm/nospec-insn.h> +#include <asm/lowcore.h> +#include <asm/machine.h> + +_LPP_OFFSET = __LC_LPP + + .macro STBEAR address + ALTERNATIVE "nop", ".insn s,0xb2010000,\address", ALT_FACILITY(193) + .endm -__PT_R0 = __PT_GPRS -__PT_R1 = __PT_GPRS + 4 -__PT_R2 = __PT_GPRS + 8 -__PT_R3 = __PT_GPRS + 12 -__PT_R4 = __PT_GPRS + 16 -__PT_R5 = __PT_GPRS + 20 -__PT_R6 = __PT_GPRS + 24 -__PT_R7 = __PT_GPRS + 28 -__PT_R8 = __PT_GPRS + 32 -__PT_R9 = __PT_GPRS + 36 -__PT_R10 = __PT_GPRS + 40 -__PT_R11 = __PT_GPRS + 44 -__PT_R12 = __PT_GPRS + 48 -__PT_R13 = __PT_GPRS + 524 -__PT_R14 = __PT_GPRS + 56 -__PT_R15 = __PT_GPRS + 60 - -_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \ - _TIF_MCCK_PENDING | _TIF_PER_TRAP ) -_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \ - _TIF_MCCK_PENDING) -_TIF_TRACE = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \ - _TIF_SYSCALL_TRACEPOINT) - -STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER -STACK_SIZE = 1 << STACK_SHIFT -STACK_INIT = STACK_SIZE - STACK_FRAME_OVERHEAD - __PT_SIZE - -#define BASED(name) name-system_call(%r13) - - .macro TRACE_IRQS_ON -#ifdef CONFIG_TRACE_IRQFLAGS - basr %r2,%r0 - l %r1,BASED(.Lhardirqs_on) - basr %r14,%r1 # call trace_hardirqs_on_caller -#endif + .macro LBEAR address + ALTERNATIVE "nop", ".insn s,0xb2000000,\address", ALT_FACILITY(193) .endm - .macro TRACE_IRQS_OFF -#ifdef CONFIG_TRACE_IRQFLAGS - basr %r2,%r0 - l %r1,BASED(.Lhardirqs_off) - basr %r14,%r1 # call trace_hardirqs_off_caller -#endif + .macro LPSWEY address, lpswe + ALTERNATIVE_2 "b \lpswe;nopr", \ + ".insn siy,0xeb0000000071,\address,0", ALT_FACILITY(193), \ + __stringify(.insn siy,0xeb0000000071,LOWCORE_ALT_ADDRESS+\address,0), \ + ALT_FEATURE(MFEATURE_LOWCORE) .endm - .macro LOCKDEP_SYS_EXIT -#ifdef CONFIG_LOCKDEP - tm __PT_PSW+1(%r11),0x01 # returning to user ? - jz .+10 - l %r1,BASED(.Llockdep_sys_exit) - basr %r14,%r1 # call lockdep_sys_exit -#endif + .macro MBEAR reg, lowcore + ALTERNATIVE "brcl 0,0", __stringify(mvc __PT_LAST_BREAK(8,\reg),__LC_LAST_BREAK(\lowcore)),\ + ALT_FACILITY(193) .endm - .macro CHECK_STACK stacksize,savearea -#ifdef CONFIG_CHECK_STACK - tml %r15,\stacksize - CONFIG_STACK_GUARD - la %r14,\savearea - jz stack_overflow -#endif + .macro CHECK_VMAP_STACK savearea, lowcore, oklabel + lgr %r14,%r15 + nill %r14,0x10000 - THREAD_SIZE + oill %r14,STACK_INIT_OFFSET + clg %r14,__LC_KERNEL_STACK(\lowcore) + je \oklabel + clg %r14,__LC_ASYNC_STACK(\lowcore) + je \oklabel + clg %r14,__LC_MCCK_STACK(\lowcore) + je \oklabel + clg %r14,__LC_NODAT_STACK(\lowcore) + je \oklabel + clg %r14,__LC_RESTART_STACK(\lowcore) + je \oklabel + la %r14,\savearea(\lowcore) + j stack_invalid .endm - .macro SWITCH_ASYNC savearea,stack,shift - tmh %r8,0x0001 # interrupting from user ? - jnz 1f - lr %r14,%r9 - sl %r14,BASED(.Lcritical_start) - cl %r14,BASED(.Lcritical_length) - jhe 0f - la %r11,\savearea # inside critical section, do cleanup - bras %r14,cleanup_critical - tmh %r8,0x0001 # retest problem state after cleanup - jnz 1f -0: l %r14,\stack # are we already on the target stack? - slr %r14,%r15 - sra %r14,\shift - jnz 1f - CHECK_STACK 1<<\shift,\savearea - ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) - j 2f -1: l %r15,\stack # load target stack -2: la %r11,STACK_FRAME_OVERHEAD(%r15) + /* + * The TSTMSK macro generates a test-under-mask instruction by + * calculating the memory offset for the specified mask value. + * Mask value can be any constant. The macro shifts the mask + * value to calculate the memory offset for the test-under-mask + * instruction. + */ + .macro TSTMSK addr, mask, size=8, bytepos=0 + .if (\bytepos < \size) && (\mask >> 8) + .if (\mask & 0xff) + .error "Mask exceeds byte boundary" + .endif + TSTMSK \addr, "(\mask >> 8)", \size, "(\bytepos + 1)" + .exitm + .endif + .ifeq \mask + .error "Mask must not be zero" + .endif + off = \size - \bytepos - 1 + tm off+\addr, \mask + .endm + + .macro BPOFF + ALTERNATIVE "nop", ".insn rrf,0xb2e80000,0,0,12,0", ALT_SPEC(82) + .endm + + .macro BPON + ALTERNATIVE "nop", ".insn rrf,0xb2e80000,0,0,13,0", ALT_SPEC(82) .endm - .macro ADD64 high,low,timer - al \high,\timer - al \low,4+\timer - brc 12,.+8 - ahi \high,1 + .macro BPENTER tif_ptr,tif_mask + ALTERNATIVE "TSTMSK \tif_ptr,\tif_mask; jz .+8; .insn rrf,0xb2e80000,0,0,13,0", \ + "j .+12; nop; nop", ALT_SPEC(82) .endm - .macro SUB64 high,low,timer - sl \high,\timer - sl \low,4+\timer - brc 3,.+8 - ahi \high,-1 + .macro BPEXIT tif_ptr,tif_mask + TSTMSK \tif_ptr,\tif_mask + ALTERNATIVE "jz .+8; .insn rrf,0xb2e80000,0,0,12,0", \ + "jnz .+8; .insn rrf,0xb2e80000,0,0,13,0", ALT_SPEC(82) .endm - .macro UPDATE_VTIME high,low,enter_timer - lm \high,\low,__LC_EXIT_TIMER - SUB64 \high,\low,\enter_timer - ADD64 \high,\low,__LC_USER_TIMER - stm \high,\low,__LC_USER_TIMER - lm \high,\low,__LC_LAST_UPDATE_TIMER - SUB64 \high,\low,__LC_EXIT_TIMER - ADD64 \high,\low,__LC_SYSTEM_TIMER - stm \high,\low,__LC_SYSTEM_TIMER - mvc __LC_LAST_UPDATE_TIMER(8),\enter_timer +#if IS_ENABLED(CONFIG_KVM) + .macro SIEEXIT sie_control,lowcore + lg %r9,\sie_control # get control block pointer + ni __SIE_PROG0C+3(%r9),0xfe # no longer in SIE + lctlg %c1,%c1,__LC_USER_ASCE(\lowcore) # load primary asce + lg %r9,__LC_CURRENT(\lowcore) + mvi __TI_sie(%r9),0 + larl %r9,sie_exit # skip forward to sie_exit .endm +#endif - .macro REENABLE_IRQS - st %r8,__LC_RETURN_PSW - ni __LC_RETURN_PSW,0xbf - ssm __LC_RETURN_PSW + .macro STACKLEAK_ERASE +#ifdef CONFIG_KSTACK_ERASE + brasl %r14,stackleak_erase_on_task_stack +#endif .endm + GEN_BR_THUNK %r14 + .section .kprobes.text, "ax" +.Ldummy: + /* + * The following nop exists only in order to avoid that the next + * symbol starts at the beginning of the kprobes text section. + * In that case there would be several symbols at the same address. + * E.g. objdump would take an arbitrary symbol when disassembling + * the code. + * With the added nop in between this cannot happen. + */ + nop 0 /* - * Scheduler resume function, called by switch_to - * gpr2 = (task_struct *) prev - * gpr3 = (task_struct *) next + * Scheduler resume function, called by __switch_to + * gpr2 = (task_struct *)prev + * gpr3 = (task_struct *)next * Returns: * gpr2 = prev */ -ENTRY(__switch_to) - stm %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task - st %r15,__THREAD_ksp(%r2) # store kernel stack of prev - l %r4,__THREAD_info(%r2) # get thread_info of prev - l %r5,__THREAD_info(%r3) # get thread_info of next - lr %r15,%r5 - ahi %r15,STACK_INIT # end of kernel stack of next - st %r3,__LC_CURRENT # store task struct of next - st %r5,__LC_THREAD_INFO # store thread info of next - st %r15,__LC_KERNEL_STACK # store end of kernel stack - 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 - l %r15,__THREAD_ksp(%r3) # load kernel stack of next - tm __TI_flags+3(%r4),_TIF_MCCK_PENDING # machine check pending? - jz 0f - ni __TI_flags+3(%r4),255-_TIF_MCCK_PENDING # clear flag in prev - oi __TI_flags+3(%r5),_TIF_MCCK_PENDING # set it in next -0: lm %r6,%r15,__SF_GPRS(%r15) # load gprs of next task - br %r14 +SYM_FUNC_START(__switch_to_asm) + stmg %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task + lghi %r4,__TASK_stack + lghi %r1,__TASK_thread + llill %r5,STACK_INIT_OFFSET + stg %r15,__THREAD_ksp(%r1,%r2) # store kernel stack of prev + lg %r15,0(%r4,%r3) # start of kernel stack of next + agr %r15,%r5 # end of kernel stack of next + GET_LC %r13 + stg %r3,__LC_CURRENT(%r13) # store task struct of next + stg %r15,__LC_KERNEL_STACK(%r13) # store end of kernel stack + lg %r15,__THREAD_ksp(%r1,%r3) # load kernel stack of next + lay %r4,__TASK_pid(%r3) + mvc __LC_CURRENT_PID(4,%r13),0(%r4) # store pid of next + ALTERNATIVE "nop", "lpp _LPP_OFFSET(%r13)", ALT_FACILITY(40) +#ifdef CONFIG_STACKPROTECTOR + lg %r3,__TASK_stack_canary(%r3) + stg %r3,__LC_STACK_CANARY(%r13) +#endif + lmg %r6,%r15,__SF_GPRS(%r15) # load gprs of next task + BR_EX %r14 +SYM_FUNC_END(__switch_to_asm) -__critical_start: +#if IS_ENABLED(CONFIG_KVM) /* - * SVC interrupt handler routine. System calls are synchronous events and - * are executed with interrupts enabled. + * __sie64a calling convention: + * %r2 pointer to sie control block phys + * %r3 pointer to sie control block virt + * %r4 guest register save area + * %r5 guest asce */ +SYM_FUNC_START(__sie64a) + stmg %r6,%r14,__SF_GPRS(%r15) # save kernel registers + GET_LC %r13 + lg %r14,__LC_CURRENT(%r13) + stg %r2,__SF_SIE_CONTROL_PHYS(%r15) # save sie block physical.. + stg %r3,__SF_SIE_CONTROL(%r15) # ...and virtual addresses + stg %r4,__SF_SIE_SAVEAREA(%r15) # save guest register save area + stg %r5,__SF_SIE_GUEST_ASCE(%r15) # save guest asce + xc __SF_SIE_REASON(8,%r15),__SF_SIE_REASON(%r15) # reason code = 0 + mvc __SF_SIE_FLAGS(8,%r15),__TI_flags(%r14) # copy thread flags + lmg %r0,%r13,0(%r4) # load guest gprs 0-13 + mvi __TI_sie(%r14),1 + stosm __SF_SIE_IRQ(%r15),0x03 # enable interrupts + lctlg %c1,%c1,__SF_SIE_GUEST_ASCE(%r15) # load primary asce + lg %r14,__SF_SIE_CONTROL(%r15) # get control block pointer + oi __SIE_PROG0C+3(%r14),1 # we are going into SIE now + tm __SIE_PROG20+3(%r14),3 # last exit... + jnz .Lsie_skip + lg %r14,__SF_SIE_CONTROL_PHYS(%r15) # get sie block phys addr + BPEXIT __SF_SIE_FLAGS(%r15),_TIF_ISOLATE_BP_GUEST +.Lsie_entry: + sie 0(%r14) +# Let the next instruction be NOP to avoid triggering a machine check +# and handling it in a guest as result of the instruction execution. + nopr 7 +.Lsie_leave: + BPOFF + BPENTER __SF_SIE_FLAGS(%r15),_TIF_ISOLATE_BP_GUEST +.Lsie_skip: + lg %r14,__SF_SIE_CONTROL(%r15) # get control block pointer + ni __SIE_PROG0C+3(%r14),0xfe # no longer in SIE + GET_LC %r14 + lctlg %c1,%c1,__LC_USER_ASCE(%r14) # load primary asce + lg %r14,__LC_CURRENT(%r14) + mvi __TI_sie(%r14),0 +SYM_INNER_LABEL(sie_exit, SYM_L_GLOBAL) + stnsm __SF_SIE_IRQ(%r15),0xfc # disable interrupts + lg %r14,__SF_SIE_SAVEAREA(%r15) # load guest register save area + stmg %r0,%r13,0(%r14) # save guest gprs 0-13 + xgr %r0,%r0 # clear guest registers to + xgr %r1,%r1 # prevent speculative use + xgr %r3,%r3 + xgr %r4,%r4 + xgr %r5,%r5 + lmg %r6,%r14,__SF_GPRS(%r15) # restore kernel registers + lg %r2,__SF_SIE_REASON(%r15) # return exit reason code + BR_EX %r14 +SYM_FUNC_END(__sie64a) +EXPORT_SYMBOL(__sie64a) +EXPORT_SYMBOL(sie_exit) +#endif -ENTRY(system_call) - stpt __LC_SYNC_ENTER_TIMER -sysc_stm: - stm %r8,%r15,__LC_SAVE_AREA_SYNC - l %r12,__LC_THREAD_INFO - l %r13,__LC_SVC_NEW_PSW+4 -sysc_per: - l %r15,__LC_KERNEL_STACK - la %r11,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs -sysc_vtime: - UPDATE_VTIME %r8,%r9,__LC_SYNC_ENTER_TIMER - stm %r0,%r7,__PT_R0(%r11) - mvc __PT_R8(32,%r11),__LC_SAVE_AREA_SYNC - mvc __PT_PSW(8,%r11),__LC_SVC_OLD_PSW - mvc __PT_INT_CODE(4,%r11),__LC_SVC_ILC -sysc_do_svc: - oi __TI_flags+3(%r12),_TIF_SYSCALL - l %r10,__TI_sysc_table(%r12) # 31 bit system call table - lh %r8,__PT_INT_CODE+2(%r11) - sla %r8,2 # shift and test for svc0 - jnz sysc_nr_ok - # svc 0: system call number in %r1 - cl %r1,BASED(.Lnr_syscalls) - jnl sysc_nr_ok - sth %r1,__PT_INT_CODE+2(%r11) - lr %r8,%r1 - sla %r8,2 -sysc_nr_ok: - xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) - st %r2,__PT_ORIG_GPR2(%r11) - st %r7,STACK_FRAME_OVERHEAD(%r15) - l %r9,0(%r8,%r10) # get system call addr. - tm __TI_flags+2(%r12),_TIF_TRACE >> 8 - jnz sysc_tracesys - basr %r14,%r9 # call sys_xxxx - st %r2,__PT_R2(%r11) # store return value - -sysc_return: - LOCKDEP_SYS_EXIT -sysc_tif: - tm __PT_PSW+1(%r11),0x01 # returning to user ? - jno sysc_restore - tm __TI_flags+3(%r12),_TIF_WORK_SVC - jnz sysc_work # check for work - ni __TI_flags+3(%r12),255-_TIF_SYSCALL -sysc_restore: - mvc __LC_RETURN_PSW(8),__PT_PSW(%r11) - stpt __LC_EXIT_TIMER - lm %r0,%r15,__PT_R0(%r11) - lpsw __LC_RETURN_PSW -sysc_done: - -# -# One of the work bits is on. Find out which one. -# -sysc_work: - tm __TI_flags+3(%r12),_TIF_MCCK_PENDING - jo sysc_mcck_pending - tm __TI_flags+3(%r12),_TIF_NEED_RESCHED - jo sysc_reschedule - tm __TI_flags+3(%r12),_TIF_PER_TRAP - jo sysc_singlestep - tm __TI_flags+3(%r12),_TIF_SIGPENDING - jo sysc_sigpending - tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME - jo sysc_notify_resume - j sysc_return # beware of critical section cleanup - -# -# _TIF_NEED_RESCHED is set, call schedule -# -sysc_reschedule: - l %r1,BASED(.Lschedule) - la %r14,BASED(sysc_return) - br %r1 # call schedule - -# -# _TIF_MCCK_PENDING is set, call handler -# -sysc_mcck_pending: - l %r1,BASED(.Lhandle_mcck) - la %r14,BASED(sysc_return) - br %r1 # TIF bit will be cleared by handler - -# -# _TIF_SIGPENDING is set, call do_signal -# -sysc_sigpending: - lr %r2,%r11 # pass pointer to pt_regs - l %r1,BASED(.Ldo_signal) - basr %r14,%r1 # call do_signal - tm __TI_flags+3(%r12),_TIF_SYSCALL - jno sysc_return - lm %r2,%r7,__PT_R2(%r11) # load svc arguments - xr %r8,%r8 # svc 0 returns -ENOSYS - clc __PT_INT_CODE+2(2,%r11),BASED(.Lnr_syscalls+2) - jnl sysc_nr_ok # invalid svc number -> do svc 0 - lh %r8,__PT_INT_CODE+2(%r11) # load new svc number - sla %r8,2 - j sysc_nr_ok # restart svc - -# -# _TIF_NOTIFY_RESUME is set, call do_notify_resume -# -sysc_notify_resume: - lr %r2,%r11 # pass pointer to pt_regs - l %r1,BASED(.Ldo_notify_resume) - la %r14,BASED(sysc_return) - br %r1 # call do_notify_resume - -# -# _TIF_PER_TRAP is set, call do_per_trap -# -sysc_singlestep: - ni __TI_flags+3(%r12),255-_TIF_PER_TRAP - lr %r2,%r11 # pass pointer to pt_regs - l %r1,BASED(.Ldo_per_trap) - la %r14,BASED(sysc_return) - br %r1 # call do_per_trap +/* + * SVC interrupt handler routine. System calls are synchronous events and + * are entered with interrupts disabled. + */ -# -# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before -# and after the system call -# -sysc_tracesys: - l %r1,BASED(.Ltrace_enter) - lr %r2,%r11 # pass pointer to pt_regs - la %r3,0 - xr %r0,%r0 - icm %r0,3,__PT_INT_CODE+2(%r11) - st %r0,__PT_R2(%r11) - basr %r14,%r1 # call do_syscall_trace_enter - cl %r2,BASED(.Lnr_syscalls) - jnl sysc_tracenogo - lr %r8,%r2 - sll %r8,2 - l %r9,0(%r8,%r10) -sysc_tracego: - lm %r3,%r7,__PT_R3(%r11) - st %r7,STACK_FRAME_OVERHEAD(%r15) - l %r2,__PT_ORIG_GPR2(%r11) - basr %r14,%r9 # call sys_xxx - st %r2,__PT_R2(%r11) # store return value -sysc_tracenogo: - tm __TI_flags+2(%r12),_TIF_TRACE >> 8 - jz sysc_return - l %r1,BASED(.Ltrace_exit) - lr %r2,%r11 # pass pointer to pt_regs - la %r14,BASED(sysc_return) - br %r1 # call do_syscall_trace_exit +SYM_CODE_START(system_call) + STMG_LC %r8,%r15,__LC_SAVE_AREA + GET_LC %r13 + stpt __LC_SYS_ENTER_TIMER(%r13) + BPOFF + lghi %r14,0 +.Lsysc_per: + STBEAR __LC_LAST_BREAK(%r13) + lg %r15,__LC_KERNEL_STACK(%r13) + xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) + stmg %r0,%r7,STACK_FRAME_OVERHEAD+__PT_R0(%r15) + # clear user controlled register to prevent speculative use + xgr %r0,%r0 + xgr %r1,%r1 + xgr %r4,%r4 + xgr %r5,%r5 + xgr %r6,%r6 + xgr %r7,%r7 + xgr %r8,%r8 + xgr %r9,%r9 + xgr %r10,%r10 + xgr %r11,%r11 + la %r2,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs + mvc __PT_R8(64,%r2),__LC_SAVE_AREA(%r13) + MBEAR %r2,%r13 + lgr %r3,%r14 + brasl %r14,__do_syscall + STACKLEAK_ERASE + mvc __LC_RETURN_PSW(16,%r13),STACK_FRAME_OVERHEAD+__PT_PSW(%r15) + BPON + LBEAR STACK_FRAME_OVERHEAD+__PT_LAST_BREAK(%r15) + stpt __LC_EXIT_TIMER(%r13) + lmg %r0,%r15,STACK_FRAME_OVERHEAD+__PT_R0(%r15) + LPSWEY __LC_RETURN_PSW,__LC_RETURN_LPSWE +SYM_CODE_END(system_call) # # a new process exits the kernel with ret_from_fork # -ENTRY(ret_from_fork) - la %r11,STACK_FRAME_OVERHEAD(%r15) - l %r12,__LC_THREAD_INFO - l %r13,__LC_SVC_NEW_PSW+4 - l %r1,BASED(.Lschedule_tail) - basr %r14,%r1 # call schedule_tail - TRACE_IRQS_ON - ssm __LC_SVC_NEW_PSW # reenable interrupts - tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ? - jne sysc_tracenogo - # it's a kernel thread - lm %r9,%r10,__PT_R9(%r11) # load gprs -ENTRY(kernel_thread_starter) - la %r2,0(%r10) - basr %r14,%r9 - j sysc_tracenogo +SYM_CODE_START(ret_from_fork) + lgr %r3,%r11 + brasl %r14,__ret_from_fork + STACKLEAK_ERASE + GET_LC %r13 + mvc __LC_RETURN_PSW(16,%r13),STACK_FRAME_OVERHEAD+__PT_PSW(%r15) + BPON + LBEAR STACK_FRAME_OVERHEAD+__PT_LAST_BREAK(%r15) + stpt __LC_EXIT_TIMER(%r13) + lmg %r0,%r15,STACK_FRAME_OVERHEAD+__PT_R0(%r15) + LPSWEY __LC_RETURN_PSW,__LC_RETURN_LPSWE +SYM_CODE_END(ret_from_fork) /* * Program check handler routine */ -ENTRY(pgm_check_handler) - stpt __LC_SYNC_ENTER_TIMER - stm %r8,%r15,__LC_SAVE_AREA_SYNC - l %r12,__LC_THREAD_INFO - l %r13,__LC_SVC_NEW_PSW+4 - lm %r8,%r9,__LC_PGM_OLD_PSW - tmh %r8,0x0001 # test problem state bit - jnz 1f # -> fault in user space - tmh %r8,0x4000 # PER bit set in old PSW ? - jnz 0f # -> enabled, can't be a double fault - tm __LC_PGM_ILC+3,0x80 # check for per exception - jnz pgm_svcper # -> single stepped svc -0: CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC - ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) - j 2f -1: UPDATE_VTIME %r14,%r15,__LC_SYNC_ENTER_TIMER - l %r15,__LC_KERNEL_STACK -2: la %r11,STACK_FRAME_OVERHEAD(%r15) - stm %r0,%r7,__PT_R0(%r11) - mvc __PT_R8(32,%r11),__LC_SAVE_AREA_SYNC - stm %r8,%r9,__PT_PSW(%r11) - mvc __PT_INT_CODE(4,%r11),__LC_PGM_ILC - mvc __PT_INT_PARM_LONG(4,%r11),__LC_TRANS_EXC_CODE - tm __LC_PGM_ILC+3,0x80 # check for per exception - jz 0f - l %r1,__TI_task(%r12) - tmh %r8,0x0001 # kernel per event ? - jz pgm_kprobe - oi __TI_flags+3(%r12),_TIF_PER_TRAP - mvc __THREAD_per_address(4,%r1),__LC_PER_ADDRESS - mvc __THREAD_per_cause(2,%r1),__LC_PER_CAUSE - mvc __THREAD_per_paid(1,%r1),__LC_PER_PAID -0: REENABLE_IRQS - xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) - l %r1,BASED(.Ljump_table) - la %r10,0x7f - n %r10,__PT_INT_CODE(%r11) - je sysc_return - sll %r10,2 - l %r1,0(%r10,%r1) # load address of handler routine - lr %r2,%r11 # pass pointer to pt_regs - basr %r14,%r1 # branch to interrupt-handler - j sysc_return - -# -# PER event in supervisor state, must be kprobes -# -pgm_kprobe: - REENABLE_IRQS - xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) - l %r1,BASED(.Ldo_per_trap) - lr %r2,%r11 # pass pointer to pt_regs - basr %r14,%r1 # call do_per_trap - j sysc_return +SYM_CODE_START(pgm_check_handler) + STMG_LC %r8,%r15,__LC_SAVE_AREA + GET_LC %r13 + stpt __LC_SYS_ENTER_TIMER(%r13) + BPOFF + lmg %r8,%r9,__LC_PGM_OLD_PSW(%r13) + xgr %r10,%r10 + tmhh %r8,0x0001 # coming from user space? + jo 3f # -> fault in user space +#if IS_ENABLED(CONFIG_KVM) + lg %r11,__LC_CURRENT(%r13) + tm __TI_sie(%r11),0xff + jz 1f + BPENTER __SF_SIE_FLAGS(%r15),_TIF_ISOLATE_BP_GUEST + SIEEXIT __SF_SIE_CONTROL(%r15),%r13 + lghi %r10,_PIF_GUEST_FAULT +#endif +1: tmhh %r8,0x4000 # PER bit set in old PSW ? + jnz 2f # -> enabled, can't be a double fault + tm __LC_PGM_ILC+3(%r13),0x80 # check for per exception + jnz .Lpgm_svcper # -> single stepped svc +2: aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) + # CHECK_VMAP_STACK branches to stack_invalid or 4f + CHECK_VMAP_STACK __LC_SAVE_AREA,%r13,4f +3: lg %r15,__LC_KERNEL_STACK(%r13) +4: la %r11,STACK_FRAME_OVERHEAD(%r15) + stg %r10,__PT_FLAGS(%r11) + xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) + stmg %r0,%r7,__PT_R0(%r11) + mvc __PT_R8(64,%r11),__LC_SAVE_AREA(%r13) + mvc __PT_LAST_BREAK(8,%r11),__LC_PGM_LAST_BREAK(%r13) + stmg %r8,%r9,__PT_PSW(%r11) + # clear user controlled registers to prevent speculative use + xgr %r0,%r0 + xgr %r1,%r1 + xgr %r3,%r3 + xgr %r4,%r4 + xgr %r5,%r5 + xgr %r6,%r6 + xgr %r7,%r7 + xgr %r12,%r12 + lgr %r2,%r11 + brasl %r14,__do_pgm_check + tmhh %r8,0x0001 # returning to user space? + jno .Lpgm_exit_kernel + STACKLEAK_ERASE + BPON + stpt __LC_EXIT_TIMER(%r13) +.Lpgm_exit_kernel: + mvc __LC_RETURN_PSW(16,%r13),STACK_FRAME_OVERHEAD+__PT_PSW(%r15) + LBEAR STACK_FRAME_OVERHEAD+__PT_LAST_BREAK(%r15) + lmg %r0,%r15,STACK_FRAME_OVERHEAD+__PT_R0(%r15) + LPSWEY __LC_RETURN_PSW,__LC_RETURN_LPSWE # # single stepped system call # -pgm_svcper: - oi __TI_flags+3(%r12),_TIF_PER_TRAP - mvc __LC_RETURN_PSW(4),__LC_SVC_NEW_PSW - mvc __LC_RETURN_PSW+4(4),BASED(.Lsysc_per) - lpsw __LC_RETURN_PSW # branch to sysc_per and enable irqs +.Lpgm_svcper: + mvc __LC_RETURN_PSW(8,%r13),__LC_SVC_NEW_PSW(%r13) + larl %r14,.Lsysc_per + stg %r14,__LC_RETURN_PSW+8(%r13) + lghi %r14,1 + LBEAR __LC_PGM_LAST_BREAK(%r13) + LPSWEY __LC_RETURN_PSW,__LC_RETURN_LPSWE # branch to .Lsysc_per +SYM_CODE_END(pgm_check_handler) /* - * IO interrupt handler routine + * Interrupt handler macro used for external and IO interrupts. */ - -ENTRY(io_int_handler) - stck __LC_INT_CLOCK - stpt __LC_ASYNC_ENTER_TIMER - stm %r8,%r15,__LC_SAVE_AREA_ASYNC - l %r12,__LC_THREAD_INFO - l %r13,__LC_SVC_NEW_PSW+4 - lm %r8,%r9,__LC_IO_OLD_PSW - tmh %r8,0x0001 # interrupting from user ? - jz io_skip - UPDATE_VTIME %r14,%r15,__LC_ASYNC_ENTER_TIMER -io_skip: - SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT - stm %r0,%r7,__PT_R0(%r11) - mvc __PT_R8(32,%r11),__LC_SAVE_AREA_ASYNC - stm %r8,%r9,__PT_PSW(%r11) - mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID - TRACE_IRQS_OFF - xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) -io_loop: - l %r1,BASED(.Ldo_IRQ) - lr %r2,%r11 # pass pointer to pt_regs - basr %r14,%r1 # call do_IRQ - tm __LC_MACHINE_FLAGS+2,0x10 # MACHINE_FLAG_LPAR - jz io_return - tpi 0 - jz io_return - mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID - j io_loop -io_return: - LOCKDEP_SYS_EXIT - TRACE_IRQS_ON -io_tif: - tm __TI_flags+3(%r12),_TIF_WORK_INT - jnz io_work # there is work to do (signals etc.) -io_restore: - mvc __LC_RETURN_PSW(8),__PT_PSW(%r11) - stpt __LC_EXIT_TIMER - lm %r0,%r15,__PT_R0(%r11) - lpsw __LC_RETURN_PSW -io_done: - -# -# There is work todo, find out in which context we have been interrupted: -# 1) if we return to user space we can do all _TIF_WORK_INT work -# 2) if we return to kernel code and preemptive scheduling is enabled check -# the preemption counter and if it is zero call preempt_schedule_irq -# Before any work can be done, a switch to the kernel stack is required. -# -io_work: - tm __PT_PSW+1(%r11),0x01 # returning to user ? - jo io_work_user # yes -> do resched & signal -#ifdef CONFIG_PREEMPT - # check for preemptive scheduling - icm %r0,15,__TI_precount(%r12) - jnz io_restore # preemption disabled - tm __TI_flags+3(%r12),_TIF_NEED_RESCHED - jno io_restore - # switch to kernel stack - l %r1,__PT_R15(%r11) - ahi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE) - mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) - xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) - la %r11,STACK_FRAME_OVERHEAD(%r1) - lr %r15,%r1 - # TRACE_IRQS_ON already done at io_return, call - # TRACE_IRQS_OFF to keep things symmetrical - TRACE_IRQS_OFF - l %r1,BASED(.Lpreempt_irq) - basr %r14,%r1 # call preempt_schedule_irq - j io_return -#else - j io_restore +.macro INT_HANDLER name,lc_old_psw,handler +SYM_CODE_START(\name) + STMG_LC %r8,%r15,__LC_SAVE_AREA + GET_LC %r13 + stckf __LC_INT_CLOCK(%r13) + stpt __LC_SYS_ENTER_TIMER(%r13) + STBEAR __LC_LAST_BREAK(%r13) + BPOFF + lmg %r8,%r9,\lc_old_psw(%r13) + tmhh %r8,0x0001 # interrupting from user ? + jnz 1f +#if IS_ENABLED(CONFIG_KVM) + lg %r10,__LC_CURRENT(%r13) + tm __TI_sie(%r10),0xff + jz 0f + BPENTER __SF_SIE_FLAGS(%r15),_TIF_ISOLATE_BP_GUEST + SIEEXIT __SF_SIE_CONTROL(%r15),%r13 #endif +0: aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) + j 2f +1: lg %r15,__LC_KERNEL_STACK(%r13) +2: xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) + la %r11,STACK_FRAME_OVERHEAD(%r15) + stmg %r0,%r7,__PT_R0(%r11) + # clear user controlled registers to prevent speculative use + xgr %r0,%r0 + xgr %r1,%r1 + xgr %r3,%r3 + xgr %r4,%r4 + xgr %r5,%r5 + xgr %r6,%r6 + xgr %r7,%r7 + xgr %r10,%r10 + xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11) + mvc __PT_R8(64,%r11),__LC_SAVE_AREA(%r13) + MBEAR %r11,%r13 + stmg %r8,%r9,__PT_PSW(%r11) + lgr %r2,%r11 # pass pointer to pt_regs + brasl %r14,\handler + mvc __LC_RETURN_PSW(16,%r13),__PT_PSW(%r11) + tmhh %r8,0x0001 # returning to user ? + jno 2f + STACKLEAK_ERASE + BPON + stpt __LC_EXIT_TIMER(%r13) +2: LBEAR __PT_LAST_BREAK(%r11) + lmg %r0,%r15,__PT_R0(%r11) + LPSWEY __LC_RETURN_PSW,__LC_RETURN_LPSWE +SYM_CODE_END(\name) +.endm + + .section .irqentry.text, "ax" + +INT_HANDLER ext_int_handler,__LC_EXT_OLD_PSW,do_ext_irq +INT_HANDLER io_int_handler,__LC_IO_OLD_PSW,do_io_irq -# -# Need to do work before returning to userspace, switch to kernel stack -# -io_work_user: - l %r1,__LC_KERNEL_STACK - mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) - xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) - la %r11,STACK_FRAME_OVERHEAD(%r1) - lr %r15,%r1 - -# -# One of the work bits is on. Find out which one. -# Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED -# and _TIF_MCCK_PENDING -# -io_work_tif: - tm __TI_flags+3(%r12),_TIF_MCCK_PENDING - jo io_mcck_pending - tm __TI_flags+3(%r12),_TIF_NEED_RESCHED - jo io_reschedule - tm __TI_flags+3(%r12),_TIF_SIGPENDING - jo io_sigpending - tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME - jo io_notify_resume - j io_return # beware of critical section cleanup - -# -# _TIF_MCCK_PENDING is set, call handler -# -io_mcck_pending: - # TRACE_IRQS_ON already done at io_return - l %r1,BASED(.Lhandle_mcck) - basr %r14,%r1 # TIF bit will be cleared by handler - TRACE_IRQS_OFF - j io_return - -# -# _TIF_NEED_RESCHED is set, call schedule -# -io_reschedule: - # TRACE_IRQS_ON already done at io_return - l %r1,BASED(.Lschedule) - ssm __LC_SVC_NEW_PSW # reenable interrupts - basr %r14,%r1 # call scheduler - ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts - TRACE_IRQS_OFF - j io_return - -# -# _TIF_SIGPENDING is set, call do_signal -# -io_sigpending: - # TRACE_IRQS_ON already done at io_return - l %r1,BASED(.Ldo_signal) - ssm __LC_SVC_NEW_PSW # reenable interrupts - lr %r2,%r11 # pass pointer to pt_regs - basr %r14,%r1 # call do_signal - ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts - TRACE_IRQS_OFF - j io_return - -# -# _TIF_SIGPENDING is set, call do_signal -# -io_notify_resume: - # TRACE_IRQS_ON already done at io_return - l %r1,BASED(.Ldo_notify_resume) - ssm __LC_SVC_NEW_PSW # reenable interrupts - lr %r2,%r11 # pass pointer to pt_regs - basr %r14,%r1 # call do_notify_resume - ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts - TRACE_IRQS_OFF - j io_return - -/* - * External interrupt handler routine - */ - -ENTRY(ext_int_handler) - stck __LC_INT_CLOCK - stpt __LC_ASYNC_ENTER_TIMER - stm %r8,%r15,__LC_SAVE_AREA_ASYNC - l %r12,__LC_THREAD_INFO - l %r13,__LC_SVC_NEW_PSW+4 - lm %r8,%r9,__LC_EXT_OLD_PSW - tmh %r8,0x0001 # interrupting from user ? - jz ext_skip - UPDATE_VTIME %r14,%r15,__LC_ASYNC_ENTER_TIMER -ext_skip: - SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT - stm %r0,%r7,__PT_R0(%r11) - mvc __PT_R8(32,%r11),__LC_SAVE_AREA_ASYNC - stm %r8,%r9,__PT_PSW(%r11) - mvc __PT_INT_CODE(4,%r11),__LC_EXT_CPU_ADDR - mvc __PT_INT_PARM(4,%r11),__LC_EXT_PARAMS - TRACE_IRQS_OFF - lr %r2,%r11 # pass pointer to pt_regs - l %r1,BASED(.Ldo_extint) - basr %r14,%r1 # call do_extint - j io_return - -/* - * Load idle PSW. The second "half" of this function is in cleanup_idle. - */ -ENTRY(psw_idle) - st %r3,__SF_EMPTY(%r15) - basr %r1,0 - la %r1,psw_idle_lpsw+4-.(%r1) - st %r1,__SF_EMPTY+4(%r15) - oi __SF_EMPTY+4(%r15),0x80 - stck __CLOCK_IDLE_ENTER(%r2) - stpt __TIMER_IDLE_ENTER(%r2) -psw_idle_lpsw: - lpsw __SF_EMPTY(%r15) - br %r14 -psw_idle_end: - -__critical_end: + .section .kprobes.text, "ax" /* * Machine check handler routines */ - -ENTRY(mcck_int_handler) - stck __LC_MCCK_CLOCK - spt __LC_CPU_TIMER_SAVE_AREA # revalidate cpu timer - lm %r0,%r15,__LC_GPREGS_SAVE_AREA # revalidate gprs - l %r12,__LC_THREAD_INFO - l %r13,__LC_SVC_NEW_PSW+4 - lm %r8,%r9,__LC_MCK_OLD_PSW - tm __LC_MCCK_CODE,0x80 # system damage? - jo mcck_panic # yes -> rest of mcck code invalid - la %r14,__LC_CPU_TIMER_SAVE_AREA - mvc __LC_MCCK_ENTER_TIMER(8),0(%r14) - tm __LC_MCCK_CODE+5,0x02 # stored cpu timer value valid? +SYM_CODE_START(mcck_int_handler) + BPOFF + GET_LC %r13 + lmg %r8,%r9,__LC_MCK_OLD_PSW(%r13) + TSTMSK __LC_MCCK_CODE(%r13),MCCK_CODE_SYSTEM_DAMAGE + jo .Lmcck_panic # yes -> rest of mcck code invalid + TSTMSK __LC_MCCK_CODE(%r13),MCCK_CODE_CR_VALID + jno .Lmcck_panic # control registers invalid -> panic + ptlb + lay %r14,__LC_CPU_TIMER_SAVE_AREA(%r13) + mvc __LC_MCCK_ENTER_TIMER(8,%r13),0(%r14) + TSTMSK __LC_MCCK_CODE(%r13),MCCK_CODE_CPU_TIMER_VALID jo 3f - la %r14,__LC_SYNC_ENTER_TIMER - clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER - jl 0f - la %r14,__LC_ASYNC_ENTER_TIMER -0: clc 0(8,%r14),__LC_EXIT_TIMER + la %r14,__LC_SYS_ENTER_TIMER(%r13) + clc 0(8,%r14),__LC_EXIT_TIMER(%r13) jl 1f - la %r14,__LC_EXIT_TIMER -1: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER + la %r14,__LC_EXIT_TIMER(%r13) +1: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER(%r13) jl 2f - la %r14,__LC_LAST_UPDATE_TIMER + la %r14,__LC_LAST_UPDATE_TIMER(%r13) 2: spt 0(%r14) - mvc __LC_MCCK_ENTER_TIMER(8),0(%r14) -3: tm __LC_MCCK_CODE+2,0x09 # mwp + ia of old psw valid? - jno mcck_panic # no -> skip cleanup critical - tm %r8,0x0001 # interrupting from user ? - jz mcck_skip - UPDATE_VTIME %r14,%r15,__LC_MCCK_ENTER_TIMER -mcck_skip: - SWITCH_ASYNC __LC_GPREGS_SAVE_AREA+32,__LC_PANIC_STACK,PAGE_SHIFT - stm %r0,%r7,__PT_R0(%r11) - mvc __PT_R8(32,%r11),__LC_GPREGS_SAVE_AREA+32 - stm %r8,%r9,__PT_PSW(%r11) - xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) - l %r1,BASED(.Ldo_machine_check) - lr %r2,%r11 # pass pointer to pt_regs - basr %r14,%r1 # call s390_do_machine_check - tm __PT_PSW+1(%r11),0x01 # returning to user ? - jno mcck_return - l %r1,__LC_KERNEL_STACK # switch to kernel stack - mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) - xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) + mvc __LC_MCCK_ENTER_TIMER(8,%r13),0(%r14) +3: TSTMSK __LC_MCCK_CODE(%r13),MCCK_CODE_PSW_MWP_VALID + jno .Lmcck_panic + tmhh %r8,0x0001 # interrupting from user ? + jnz .Lmcck_user + TSTMSK __LC_MCCK_CODE(%r13),MCCK_CODE_PSW_IA_VALID + jno .Lmcck_panic +#if IS_ENABLED(CONFIG_KVM) + lg %r10,__LC_CURRENT(%r13) + tm __TI_sie(%r10),0xff + jz .Lmcck_user + # Need to compare the address instead of __TI_SIE flag. + # Otherwise there would be a race between setting the flag + # and entering SIE (or leaving and clearing the flag). This + # would cause machine checks targeted at the guest to be + # handled by the host. + larl %r14,.Lsie_entry + clgrjl %r9,%r14, 4f + larl %r14,.Lsie_leave + clgrjhe %r9,%r14, 4f + lg %r10,__LC_PCPU(%r13) + oi __PCPU_FLAGS+7(%r10), _CIF_MCCK_GUEST +4: BPENTER __SF_SIE_FLAGS(%r15),_TIF_ISOLATE_BP_GUEST + SIEEXIT __SF_SIE_CONTROL(%r15),%r13 +#endif +.Lmcck_user: + lg %r15,__LC_MCCK_STACK(%r13) la %r11,STACK_FRAME_OVERHEAD(%r15) - lr %r15,%r1 - ssm __LC_PGM_NEW_PSW # turn dat on, keep irqs off - tm __TI_flags+3(%r12),_TIF_MCCK_PENDING - jno mcck_return - TRACE_IRQS_OFF - l %r1,BASED(.Lhandle_mcck) - basr %r14,%r1 # call s390_handle_mcck - TRACE_IRQS_ON -mcck_return: - mvc __LC_RETURN_MCCK_PSW(8),__PT_PSW(%r11) # move return PSW - tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ? + xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) + lay %r14,__LC_GPREGS_SAVE_AREA(%r13) + mvc __PT_R0(128,%r11),0(%r14) + # clear user controlled registers to prevent speculative use + xgr %r0,%r0 + xgr %r1,%r1 + xgr %r3,%r3 + xgr %r4,%r4 + xgr %r5,%r5 + xgr %r6,%r6 + xgr %r7,%r7 + xgr %r10,%r10 + stmg %r8,%r9,__PT_PSW(%r11) + xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11) + xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) + lgr %r2,%r11 # pass pointer to pt_regs + brasl %r14,s390_do_machine_check + lmg %r0,%r10,__PT_R0(%r11) + mvc __LC_RETURN_MCCK_PSW(16,%r13),__PT_PSW(%r11) # move return PSW + tm __LC_RETURN_MCCK_PSW+1(%r13),0x01 # returning to user ? jno 0f - lm %r0,%r15,__PT_R0(%r11) - stpt __LC_EXIT_TIMER - lpsw __LC_RETURN_MCCK_PSW -0: lm %r0,%r15,__PT_R0(%r11) - lpsw __LC_RETURN_MCCK_PSW - -mcck_panic: - l %r14,__LC_PANIC_STACK - slr %r14,%r15 - sra %r14,PAGE_SHIFT + BPON + stpt __LC_EXIT_TIMER(%r13) +0: ALTERNATIVE "brcl 0,0", __stringify(lay %r12,__LC_LAST_BREAK_SAVE_AREA(%r13)),\ + ALT_FACILITY(193) + LBEAR 0(%r12) + lmg %r11,%r15,__PT_R11(%r11) + LPSWEY __LC_RETURN_MCCK_PSW,__LC_RETURN_MCCK_LPSWE + +.Lmcck_panic: + /* + * Iterate over all possible CPU addresses in the range 0..0xffff + * and stop each CPU using signal processor. Use compare and swap + * to allow just one CPU-stopper and prevent concurrent CPUs from + * stopping each other while leaving the others running. + */ + lhi %r5,0 + lhi %r6,1 + larl %r7,stop_lock + cs %r5,%r6,0(%r7) # single CPU-stopper only + jnz 4f + larl %r7,this_cpu + stap 0(%r7) # this CPU address + lh %r4,0(%r7) + nilh %r4,0 + lhi %r0,1 + sll %r0,16 # CPU counter + lhi %r3,0 # next CPU address +0: cr %r3,%r4 + je 2f +1: sigp %r1,%r3,SIGP_STOP # stop next CPU + brc SIGP_CC_BUSY,1b +2: ahi %r3,1 + brct %r0,0b +3: sigp %r1,%r4,SIGP_STOP # stop this CPU + brc SIGP_CC_BUSY,3b +4: j 4b +SYM_CODE_END(mcck_int_handler) + +SYM_CODE_START(restart_int_handler) + ALTERNATIVE "nop", "lpp _LPP_OFFSET", ALT_FACILITY(40) + stg %r15,__LC_SAVE_AREA_RESTART + TSTMSK __LC_RESTART_FLAGS,RESTART_FLAG_CTLREGS,4 jz 0f - l %r15,__LC_PANIC_STACK - j mcck_skip -0: ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) - j mcck_skip - -# -# PSW restart interrupt handler -# -ENTRY(restart_int_handler) - st %r15,__LC_SAVE_AREA_RESTART - l %r15,__LC_RESTART_STACK - ahi %r15,-__PT_SIZE # create pt_regs on stack - xc 0(__PT_SIZE,%r15),0(%r15) - stm %r0,%r14,__PT_R0(%r15) - mvc __PT_R15(4,%r15),__LC_SAVE_AREA_RESTART - mvc __PT_PSW(8,%r15),__LC_RST_OLD_PSW # store restart old psw - ahi %r15,-STACK_FRAME_OVERHEAD # create stack frame on stack + lctlg %c0,%c15,__LC_CREGS_SAVE_AREA +0: larl %r15,daton_psw + lpswe 0(%r15) # turn dat on, keep irqs off +.Ldaton: + GET_LC %r15 + lg %r15,__LC_RESTART_STACK(%r15) + xc STACK_FRAME_OVERHEAD(__PT_SIZE,%r15),STACK_FRAME_OVERHEAD(%r15) + stmg %r0,%r14,STACK_FRAME_OVERHEAD+__PT_R0(%r15) + GET_LC %r13 + mvc STACK_FRAME_OVERHEAD+__PT_R15(8,%r15),__LC_SAVE_AREA_RESTART(%r13) + mvc STACK_FRAME_OVERHEAD+__PT_PSW(16,%r15),__LC_RST_OLD_PSW(%r13) xc 0(STACK_FRAME_OVERHEAD,%r15),0(%r15) - l %r1,__LC_RESTART_FN # load fn, parm & source cpu - l %r2,__LC_RESTART_DATA - l %r3,__LC_RESTART_SOURCE - ltr %r3,%r3 # test source cpu address + lg %r1,__LC_RESTART_FN(%r13) # load fn, parm & source cpu + lg %r2,__LC_RESTART_DATA(%r13) + lgf %r3,__LC_RESTART_SOURCE(%r13) + ltgr %r3,%r3 # test source cpu address jm 1f # negative -> skip source stop 0: sigp %r4,%r3,SIGP_SENSE # sigp sense to source cpu brc 10,0b # wait for status stored 1: basr %r14,%r1 # call function stap __SF_EMPTY(%r15) # store cpu address - lh %r3,__SF_EMPTY(%r15) + llgh %r3,__SF_EMPTY(%r15) 2: sigp %r4,%r3,SIGP_STOP # sigp stop to current cpu brc 2,2b 3: j 3b +SYM_CODE_END(restart_int_handler) + + __INIT +SYM_CODE_START(early_pgm_check_handler) + STMG_LC %r8,%r15,__LC_SAVE_AREA + GET_LC %r13 + aghi %r15,-(STACK_FRAME_OVERHEAD+__PT_SIZE) + la %r11,STACK_FRAME_OVERHEAD(%r15) + xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) + stmg %r0,%r7,__PT_R0(%r11) + mvc __PT_PSW(16,%r11),__LC_PGM_OLD_PSW(%r13) + mvc __PT_R8(64,%r11),__LC_SAVE_AREA(%r13) + lgr %r2,%r11 + brasl %r14,__do_early_pgm_check + mvc __LC_RETURN_PSW(16,%r13),STACK_FRAME_OVERHEAD+__PT_PSW(%r15) + lmg %r0,%r15,STACK_FRAME_OVERHEAD+__PT_R0(%r15) + LPSWEY __LC_RETURN_PSW,__LC_RETURN_LPSWE +SYM_CODE_END(early_pgm_check_handler) + __FINIT .section .kprobes.text, "ax" -#ifdef CONFIG_CHECK_STACK /* - * The synchronous or the asynchronous stack overflowed. We are dead. + * The synchronous or the asynchronous stack pointer is invalid. We are dead. * No need to properly save the registers, we are going to panic anyway. * Setup a pt_regs so that show_trace can provide a good call trace. */ -stack_overflow: - l %r15,__LC_PANIC_STACK # change to panic stack +SYM_CODE_START(stack_invalid) + GET_LC %r15 + lg %r15,__LC_NODAT_STACK(%r15) # change to panic stack la %r11,STACK_FRAME_OVERHEAD(%r15) - stm %r0,%r7,__PT_R0(%r11) - stm %r8,%r9,__PT_PSW(%r11) - mvc __PT_R8(32,%r11),0(%r14) - l %r1,BASED(1f) - xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) - lr %r2,%r11 # pass pointer to pt_regs - br %r1 # branch to kernel_stack_overflow -1: .long kernel_stack_overflow -#endif - -cleanup_table: - .long system_call + 0x80000000 - .long sysc_do_svc + 0x80000000 - .long sysc_tif + 0x80000000 - .long sysc_restore + 0x80000000 - .long sysc_done + 0x80000000 - .long io_tif + 0x80000000 - .long io_restore + 0x80000000 - .long io_done + 0x80000000 - .long psw_idle + 0x80000000 - .long psw_idle_end + 0x80000000 - -cleanup_critical: - cl %r9,BASED(cleanup_table) # system_call - jl 0f - cl %r9,BASED(cleanup_table+4) # sysc_do_svc - jl cleanup_system_call - cl %r9,BASED(cleanup_table+8) # sysc_tif - jl 0f - cl %r9,BASED(cleanup_table+12) # sysc_restore - jl cleanup_sysc_tif - cl %r9,BASED(cleanup_table+16) # sysc_done - jl cleanup_sysc_restore - cl %r9,BASED(cleanup_table+20) # io_tif - jl 0f - cl %r9,BASED(cleanup_table+24) # io_restore - jl cleanup_io_tif - cl %r9,BASED(cleanup_table+28) # io_done - jl cleanup_io_restore - cl %r9,BASED(cleanup_table+32) # psw_idle - jl 0f - cl %r9,BASED(cleanup_table+36) # psw_idle_end - jl cleanup_idle -0: br %r14 - -cleanup_system_call: - # check if stpt has been executed - cl %r9,BASED(cleanup_system_call_insn) - jh 0f - mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER - chi %r11,__LC_SAVE_AREA_ASYNC - je 0f - mvc __LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER -0: # check if stm has been executed - cl %r9,BASED(cleanup_system_call_insn+4) - jh 0f - mvc __LC_SAVE_AREA_SYNC(32),0(%r11) -0: # set up saved registers r12, and r13 - st %r12,16(%r11) # r12 thread-info pointer - st %r13,20(%r11) # r13 literal-pool pointer - # check if the user time calculation has been done - cl %r9,BASED(cleanup_system_call_insn+8) - jh 0f - l %r10,__LC_EXIT_TIMER - l %r15,__LC_EXIT_TIMER+4 - SUB64 %r10,%r15,__LC_SYNC_ENTER_TIMER - ADD64 %r10,%r15,__LC_USER_TIMER - st %r10,__LC_USER_TIMER - st %r15,__LC_USER_TIMER+4 -0: # check if the system time calculation has been done - cl %r9,BASED(cleanup_system_call_insn+12) - jh 0f - l %r10,__LC_LAST_UPDATE_TIMER - l %r15,__LC_LAST_UPDATE_TIMER+4 - SUB64 %r10,%r15,__LC_EXIT_TIMER - ADD64 %r10,%r15,__LC_SYSTEM_TIMER - st %r10,__LC_SYSTEM_TIMER - st %r15,__LC_SYSTEM_TIMER+4 -0: # update accounting time stamp - mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER - # set up saved register 11 - l %r15,__LC_KERNEL_STACK - la %r9,STACK_FRAME_OVERHEAD(%r15) - st %r9,12(%r11) # r11 pt_regs pointer - # fill pt_regs - mvc __PT_R8(32,%r9),__LC_SAVE_AREA_SYNC - stm %r0,%r7,__PT_R0(%r9) - mvc __PT_PSW(8,%r9),__LC_SVC_OLD_PSW - mvc __PT_INT_CODE(4,%r9),__LC_SVC_ILC - # setup saved register 15 - st %r15,28(%r11) # r15 stack pointer - # set new psw address and exit - l %r9,BASED(cleanup_table+4) # sysc_do_svc + 0x80000000 - br %r14 -cleanup_system_call_insn: - .long system_call + 0x80000000 - .long sysc_stm + 0x80000000 - .long sysc_vtime + 0x80000000 + 36 - .long sysc_vtime + 0x80000000 + 76 - -cleanup_sysc_tif: - l %r9,BASED(cleanup_table+8) # sysc_tif + 0x80000000 - br %r14 - -cleanup_sysc_restore: - cl %r9,BASED(cleanup_sysc_restore_insn) - jhe 0f - l %r9,12(%r11) # get saved pointer to pt_regs - mvc __LC_RETURN_PSW(8),__PT_PSW(%r9) - mvc 0(32,%r11),__PT_R8(%r9) - lm %r0,%r7,__PT_R0(%r9) -0: lm %r8,%r9,__LC_RETURN_PSW - br %r14 -cleanup_sysc_restore_insn: - .long sysc_done - 4 + 0x80000000 - -cleanup_io_tif: - l %r9,BASED(cleanup_table+20) # io_tif + 0x80000000 - br %r14 - -cleanup_io_restore: - cl %r9,BASED(cleanup_io_restore_insn) - jhe 0f - l %r9,12(%r11) # get saved r11 pointer to pt_regs - mvc __LC_RETURN_PSW(8),__PT_PSW(%r9) - mvc 0(32,%r11),__PT_R8(%r9) - lm %r0,%r7,__PT_R0(%r9) -0: lm %r8,%r9,__LC_RETURN_PSW - br %r14 -cleanup_io_restore_insn: - .long io_done - 4 + 0x80000000 - -cleanup_idle: - # copy interrupt clock & cpu timer - mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_INT_CLOCK - mvc __TIMER_IDLE_EXIT(8,%r2),__LC_ASYNC_ENTER_TIMER - chi %r11,__LC_SAVE_AREA_ASYNC - je 0f - mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_MCCK_CLOCK - mvc __TIMER_IDLE_EXIT(8,%r2),__LC_MCCK_ENTER_TIMER -0: # check if stck has been executed - cl %r9,BASED(cleanup_idle_insn) - jhe 1f - mvc __CLOCK_IDLE_ENTER(8,%r2),__CLOCK_IDLE_EXIT(%r2) - mvc __TIMER_IDLE_ENTER(8,%r2),__TIMER_IDLE_EXIT(%r3) -1: # account system time going idle - lm %r9,%r10,__LC_STEAL_TIMER - ADD64 %r9,%r10,__CLOCK_IDLE_ENTER(%r2) - SUB64 %r9,%r10,__LC_LAST_UPDATE_CLOCK - stm %r9,%r10,__LC_STEAL_TIMER - mvc __LC_LAST_UPDATE_CLOCK(8),__CLOCK_IDLE_EXIT(%r2) - lm %r9,%r10,__LC_SYSTEM_TIMER - ADD64 %r9,%r10,__LC_LAST_UPDATE_TIMER - SUB64 %r9,%r10,__TIMER_IDLE_ENTER(%r2) - stm %r9,%r10,__LC_SYSTEM_TIMER - mvc __LC_LAST_UPDATE_TIMER(8),__TIMER_IDLE_EXIT(%r2) - # prepare return psw - n %r8,BASED(cleanup_idle_wait) # clear wait state bit - l %r9,24(%r11) # return from psw_idle - br %r14 -cleanup_idle_insn: - .long psw_idle_lpsw + 0x80000000 -cleanup_idle_wait: - .long 0xfffdffff - -/* - * Integer constants - */ - .align 4 -.Lnr_syscalls: - .long NR_syscalls -.Lvtimer_max: - .quad 0x7fffffffffffffff - -/* - * Symbol constants - */ -.Ldo_machine_check: .long s390_do_machine_check -.Lhandle_mcck: .long s390_handle_mcck -.Ldo_IRQ: .long do_IRQ -.Ldo_extint: .long do_extint -.Ldo_signal: .long do_signal -.Ldo_notify_resume: .long do_notify_resume -.Ldo_per_trap: .long do_per_trap -.Ljump_table: .long pgm_check_table -.Lschedule: .long schedule -#ifdef CONFIG_PREEMPT -.Lpreempt_irq: .long preempt_schedule_irq -#endif -.Ltrace_enter: .long do_syscall_trace_enter -.Ltrace_exit: .long do_syscall_trace_exit -.Lschedule_tail: .long schedule_tail -.Lsysc_per: .long sysc_per + 0x80000000 -#ifdef CONFIG_TRACE_IRQFLAGS -.Lhardirqs_on: .long trace_hardirqs_on_caller -.Lhardirqs_off: .long trace_hardirqs_off_caller -#endif -#ifdef CONFIG_LOCKDEP -.Llockdep_sys_exit: .long lockdep_sys_exit -#endif -.Lcritical_start: .long __critical_start + 0x80000000 -.Lcritical_length: .long __critical_end - __critical_start - - .section .rodata, "a" -#define SYSCALL(esa,esame,emu) .long esa - .globl sys_call_table -sys_call_table: -#include "syscalls.S" -#undef SYSCALL + stmg %r0,%r7,__PT_R0(%r11) + stmg %r8,%r9,__PT_PSW(%r11) + mvc __PT_R8(64,%r11),0(%r14) + GET_LC %r2 + mvc __PT_ORIG_GPR2(8,%r11),__LC_PGM_LAST_BREAK(%r2) + xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) + lgr %r2,%r11 # pass pointer to pt_regs + jg kernel_stack_invalid +SYM_CODE_END(stack_invalid) + + .section .data, "aw" + .balign 4 +SYM_DATA_LOCAL(stop_lock, .long 0) +SYM_DATA_LOCAL(this_cpu, .short 0) + .balign 8 +SYM_DATA_START_LOCAL(daton_psw) + .quad PSW_KERNEL_BITS + .quad .Ldaton +SYM_DATA_END(daton_psw) |