From f38b0a743904cc785f5ba0d65dd1f60e17e80387 Mon Sep 17 00:00:00 2001 From: Vasily Gorbik Date: Thu, 24 Sep 2020 17:12:08 +0200 Subject: [PATCH] s390: remove unused s390_base_ext_handler s390_base_ext_handler_fn haven't been used since its introduction in commit ab14de6c37fa ("[S390] Convert memory detection into C code."). s390_base_ext_handler itself is currently falsely storing 16 registers at __LC_SAVE_AREA_ASYNC rewriting several following lowcore values: cpu_flags, return_psw, return_mcck_psw, sync_enter_timer and async_enter_timer. Besides that s390_base_ext_handler itself is only potentially hiding EXT interrupts which should not have happen in the first place. Any piece of code which requires EXT interrupts before fully functional ext_int_handler is enabled has to do it on its own, like this is done by sclp_early_cmd() which is doing EXT interrupts handling synchronously in sclp_early_wait_irq(). With s390_base_ext_handler removed unexpected EXT interrupt leads to disabled wait with the address 0x1b0 (__LC_EXT_NEW_PSW), which is currently setup in the decompressor. Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik Signed-off-by: Heiko Carstens --- arch/s390/include/asm/processor.h | 6 +----- arch/s390/kernel/base.S | 22 ---------------------- arch/s390/kernel/early.c | 4 +--- 3 files changed, 2 insertions(+), 30 deletions(-) diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index 962da04234af4..2043c562ec551 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -318,14 +318,10 @@ static __always_inline void __noreturn disabled_wait(void) } /* - * Basic Machine Check/Program Check Handler. + * Basic Program Check Handler. */ - extern void s390_base_pgm_handler(void); -extern void s390_base_ext_handler(void); - extern void (*s390_base_pgm_handler_fn)(void); -extern void (*s390_base_ext_handler_fn)(void); #define ARCH_LOW_ADDRESS_LIMIT 0x7fffffffUL diff --git a/arch/s390/kernel/base.S b/arch/s390/kernel/base.S index b79e0fd571f83..d255c69c17795 100644 --- a/arch/s390/kernel/base.S +++ b/arch/s390/kernel/base.S @@ -11,32 +11,10 @@ #include #include #include -#include GEN_BR_THUNK %r9 GEN_BR_THUNK %r14 -ENTRY(s390_base_ext_handler) - stmg %r0,%r15,__LC_SAVE_AREA_ASYNC - basr %r13,0 -0: aghi %r15,-STACK_FRAME_OVERHEAD - larl %r1,s390_base_ext_handler_fn - lg %r9,0(%r1) - ltgr %r9,%r9 - jz 1f - BASR_EX %r14,%r9 -1: lmg %r0,%r15,__LC_SAVE_AREA_ASYNC - ni __LC_EXT_OLD_PSW+1,0xfd # clear wait state bit - lpswe __LC_EXT_OLD_PSW -ENDPROC(s390_base_ext_handler) - - .section .bss - .align 8 - .globl s390_base_ext_handler_fn -s390_base_ext_handler_fn: - .quad 0 - .previous - ENTRY(s390_base_pgm_handler) stmg %r0,%r15,__LC_SAVE_AREA_SYNC basr %r13,0 diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c index 705844f739345..cc89763a4d3cf 100644 --- a/arch/s390/kernel/early.c +++ b/arch/s390/kernel/early.c @@ -169,12 +169,10 @@ static noinline __init void setup_lowcore_early(void) { psw_t psw; + psw.addr = (unsigned long)s390_base_pgm_handler; psw.mask = PSW_MASK_BASE | PSW_DEFAULT_KEY | PSW_MASK_EA | PSW_MASK_BA; if (IS_ENABLED(CONFIG_KASAN)) psw.mask |= PSW_MASK_DAT; - psw.addr = (unsigned long) s390_base_ext_handler; - S390_lowcore.external_new_psw = psw; - psw.addr = (unsigned long) s390_base_pgm_handler; S390_lowcore.program_new_psw = psw; s390_base_pgm_handler_fn = early_pgm_check_handler; S390_lowcore.preempt_count = INIT_PREEMPT_COUNT; -- 2.30.2