From f39a8c4a22ea104c368361b9ae0f550da161db2d Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Wed, 2 Nov 2022 15:18:45 +0100 Subject: [PATCH] s390/extable: add EX_TABLE_UA_LOAD_REGPAIR() macro Add new exception table type which is able to handle register pairs. If an exception is recognized on such an instruction the specified register pair will be zeroed, and the specified error register will be modified so it contains -EFAULT, similar to the existing EX_TABLE_UA_LOAD_REG() macro. Link: https://lore.kernel.org/r/Y2J8RSW2khWLgpPo@osiris Signed-off-by: Heiko Carstens --- arch/s390/include/asm/asm-extable.h | 4 ++++ arch/s390/mm/extable.c | 9 +++++++-- 2 files changed, 11 insertions(+), 2 deletions(-) diff --git a/arch/s390/include/asm/asm-extable.h b/arch/s390/include/asm/asm-extable.h index b74f1070ddb25..55a02a153dfc6 100644 --- a/arch/s390/include/asm/asm-extable.h +++ b/arch/s390/include/asm/asm-extable.h @@ -12,6 +12,7 @@ #define EX_TYPE_UA_STORE 3 #define EX_TYPE_UA_LOAD_MEM 4 #define EX_TYPE_UA_LOAD_REG 5 +#define EX_TYPE_UA_LOAD_REGPAIR 6 #define EX_DATA_REG_ERR_SHIFT 0 #define EX_DATA_REG_ERR GENMASK(3, 0) @@ -85,4 +86,7 @@ #define EX_TABLE_UA_LOAD_REG(_fault, _target, _regerr, _regzero) \ __EX_TABLE_UA(__ex_table, _fault, _target, EX_TYPE_UA_LOAD_REG, _regerr, _regzero, 0) +#define EX_TABLE_UA_LOAD_REGPAIR(_fault, _target, _regerr, _regzero) \ + __EX_TABLE_UA(__ex_table, _fault, _target, EX_TYPE_UA_LOAD_REGPAIR, _regerr, _regzero, 0) + #endif /* __ASM_EXTABLE_H */ diff --git a/arch/s390/mm/extable.c b/arch/s390/mm/extable.c index 1e4d2187541a3..fe87291df95d3 100644 --- a/arch/s390/mm/extable.c +++ b/arch/s390/mm/extable.c @@ -47,13 +47,16 @@ static bool ex_handler_ua_load_mem(const struct exception_table_entry *ex, struc return true; } -static bool ex_handler_ua_load_reg(const struct exception_table_entry *ex, struct pt_regs *regs) +static bool ex_handler_ua_load_reg(const struct exception_table_entry *ex, + bool pair, struct pt_regs *regs) { unsigned int reg_zero = FIELD_GET(EX_DATA_REG_ADDR, ex->data); unsigned int reg_err = FIELD_GET(EX_DATA_REG_ERR, ex->data); regs->gprs[reg_err] = -EFAULT; regs->gprs[reg_zero] = 0; + if (pair) + regs->gprs[reg_zero + 1] = 0; regs->psw.addr = extable_fixup(ex); return true; } @@ -75,7 +78,9 @@ bool fixup_exception(struct pt_regs *regs) case EX_TYPE_UA_LOAD_MEM: return ex_handler_ua_load_mem(ex, regs); case EX_TYPE_UA_LOAD_REG: - return ex_handler_ua_load_reg(ex, regs); + return ex_handler_ua_load_reg(ex, false, regs); + case EX_TYPE_UA_LOAD_REGPAIR: + return ex_handler_ua_load_reg(ex, true, regs); } panic("invalid exception table entry"); } -- 2.30.2