From ee3daf7c05e70a0b88723ceb18587aed75716729 Mon Sep 17 00:00:00 2001 From: Sven Schnelle Date: Wed, 28 Aug 2024 13:50:04 +0200 Subject: s390/entry: Unify save_area_sync and save_area_async In the past two save areas existed because interrupt handlers and system call / program check handlers where entered with interrupts enabled. To prevent a handler from overwriting the save areas from the previous handler, interrupts used the async save area, while system call and program check handler used the sync save area. Since the removal of critical section cleanup from entry.S, handlers are entered with interrupts disabled. When the interrupts are re-enabled, the save area is no longer need. Therefore merge both save areas into one. Reviewed-by: Heiko Carstens Reviewed-by: Alexander Gordeev Signed-off-by: Sven Schnelle Signed-off-by: Vasily Gorbik --- arch/s390/boot/head.S | 4 ++-- arch/s390/include/asm/lowcore.h | 4 ++-- arch/s390/kernel/asm-offsets.c | 3 +-- arch/s390/kernel/entry.S | 22 +++++++++++----------- 4 files changed, 16 insertions(+), 17 deletions(-) (limited to 'arch') diff --git a/arch/s390/boot/head.S b/arch/s390/boot/head.S index 637c29c3f6e3..0a47b16f6412 100644 --- a/arch/s390/boot/head.S +++ b/arch/s390/boot/head.S @@ -299,11 +299,11 @@ SYM_CODE_END(startup_normal) # the save area and does disabled wait with a faulty address. # SYM_CODE_START_LOCAL(startup_pgm_check_handler) - stmg %r8,%r15,__LC_SAVE_AREA_SYNC + stmg %r8,%r15,__LC_SAVE_AREA la %r8,4095 stctg %c0,%c15,__LC_CREGS_SAVE_AREA-4095(%r8) stmg %r0,%r7,__LC_GPREGS_SAVE_AREA-4095(%r8) - mvc __LC_GPREGS_SAVE_AREA-4095+64(64,%r8),__LC_SAVE_AREA_SYNC + mvc __LC_GPREGS_SAVE_AREA-4095+64(64,%r8),__LC_SAVE_AREA mvc __LC_PSW_SAVE_AREA-4095(16,%r8),__LC_PGM_OLD_PSW mvc __LC_RETURN_PSW(16),__LC_PGM_OLD_PSW ni __LC_RETURN_PSW,0xfc # remove IO and EX bits diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h index 183ac29afaf8..48c64716d1f2 100644 --- a/arch/s390/include/asm/lowcore.h +++ b/arch/s390/include/asm/lowcore.h @@ -98,8 +98,8 @@ struct lowcore { psw_t io_new_psw; /* 0x01f0 */ /* Save areas. */ - __u64 save_area_sync[8]; /* 0x0200 */ - __u64 save_area_async[8]; /* 0x0240 */ + __u64 save_area[8]; /* 0x0200 */ + __u8 pad_0x0240[0x0280-0x0240]; /* 0x0240 */ __u64 save_area_restart[1]; /* 0x0280 */ __u64 pcpu; /* 0x0288 */ diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c index ffa0dd2dbaac..5529248d84fb 100644 --- a/arch/s390/kernel/asm-offsets.c +++ b/arch/s390/kernel/asm-offsets.c @@ -112,8 +112,7 @@ int main(void) OFFSET(__LC_MCK_NEW_PSW, lowcore, mcck_new_psw); OFFSET(__LC_IO_NEW_PSW, lowcore, io_new_psw); /* software defined lowcore locations 0x200 - 0xdff*/ - OFFSET(__LC_SAVE_AREA_SYNC, lowcore, save_area_sync); - OFFSET(__LC_SAVE_AREA_ASYNC, lowcore, save_area_async); + OFFSET(__LC_SAVE_AREA, lowcore, save_area); OFFSET(__LC_SAVE_AREA_RESTART, lowcore, save_area_restart); OFFSET(__LC_PCPU, lowcore, pcpu); OFFSET(__LC_RETURN_PSW, lowcore, return_psw); diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S index 36424e53d63b..42ac4145dfe0 100644 --- a/arch/s390/kernel/entry.S +++ b/arch/s390/kernel/entry.S @@ -264,7 +264,7 @@ EXPORT_SYMBOL(sie_exit) */ SYM_CODE_START(system_call) - STMG_LC %r8,%r15,__LC_SAVE_AREA_SYNC + STMG_LC %r8,%r15,__LC_SAVE_AREA GET_LC %r13 stpt __LC_SYS_ENTER_TIMER(%r13) BPOFF @@ -287,7 +287,7 @@ SYM_CODE_START(system_call) xgr %r10,%r10 xgr %r11,%r11 la %r2,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs - mvc __PT_R8(64,%r2),__LC_SAVE_AREA_SYNC(%r13) + mvc __PT_R8(64,%r2),__LC_SAVE_AREA(%r13) MBEAR %r2,%r13 lgr %r3,%r14 brasl %r14,__do_syscall @@ -323,7 +323,7 @@ SYM_CODE_END(ret_from_fork) */ SYM_CODE_START(pgm_check_handler) - STMG_LC %r8,%r15,__LC_SAVE_AREA_SYNC + STMG_LC %r8,%r15,__LC_SAVE_AREA GET_LC %r13 stpt __LC_SYS_ENTER_TIMER(%r13) BPOFF @@ -338,16 +338,16 @@ SYM_CODE_START(pgm_check_handler) 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: CHECK_STACK __LC_SAVE_AREA_SYNC,%r13 +2: CHECK_STACK __LC_SAVE_AREA,%r13 aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) # CHECK_VMAP_STACK branches to stack_overflow or 4f - CHECK_VMAP_STACK __LC_SAVE_AREA_SYNC,%r13,4f + CHECK_VMAP_STACK __LC_SAVE_AREA,%r13,4f 3: lg %r15,__LC_KERNEL_STACK(%r13) 4: la %r11,STACK_FRAME_OVERHEAD(%r15) xc __PT_FLAGS(8,%r11),__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_SYNC(%r13) + mvc __PT_R8(64,%r11),__LC_SAVE_AREA(%r13) mvc __PT_LAST_BREAK(8,%r11),__LC_PGM_LAST_BREAK(%r13) stctg %c1,%c1,__PT_CR1(%r11) #if IS_ENABLED(CONFIG_KVM) @@ -398,7 +398,7 @@ SYM_CODE_END(pgm_check_handler) */ .macro INT_HANDLER name,lc_old_psw,handler SYM_CODE_START(\name) - STMG_LC %r8,%r15,__LC_SAVE_AREA_ASYNC + STMG_LC %r8,%r15,__LC_SAVE_AREA GET_LC %r13 stckf __LC_INT_CLOCK(%r13) stpt __LC_SYS_ENTER_TIMER(%r13) @@ -414,7 +414,7 @@ SYM_CODE_START(\name) BPENTER __SF_SIE_FLAGS(%r15),_TIF_ISOLATE_BP_GUEST SIEEXIT __SF_SIE_CONTROL(%r15),%r13 #endif -0: CHECK_STACK __LC_SAVE_AREA_ASYNC,%r13 +0: CHECK_STACK __LC_SAVE_AREA,%r13 aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) j 2f 1: lctlg %c1,%c1,__LC_KERNEL_ASCE(%r13) @@ -432,7 +432,7 @@ SYM_CODE_START(\name) xgr %r7,%r7 xgr %r10,%r10 xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11) - mvc __PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC(%r13) + 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 @@ -601,14 +601,14 @@ SYM_CODE_END(restart_int_handler) __INIT SYM_CODE_START(early_pgm_check_handler) - STMG_LC %r8,%r15,__LC_SAVE_AREA_SYNC + 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_SYNC(%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) -- cgit