From 6c6a07fc7c98f31fffb0a00d2d7a5344df8b4ba8 Mon Sep 17 00:00:00 2001 From: Sven Schnelle Date: Wed, 5 May 2021 22:01:11 +0200 Subject: [PATCH] s390/irq: add union/struct to access external interrupt parameters gcc-11 warns: arch/s390/kernel/irq.c: In function do_ext_irq: arch/s390/kernel/irq.c:175:9: warning: memcpy reading 4 bytes from a region of size 0 [-Wstringop-overread] 175 | memcpy(®s->int_code, &S390_lowcore.ext_cpu_addr, 4); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fix this by adding a struct for int_code to struct lowcore. Signed-off-by: Sven Schnelle Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik --- arch/s390/include/asm/lowcore.h | 9 +++++++-- arch/s390/kernel/irq.c | 2 +- 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h index a6f0b8feb12e5..d08813c7f4625 100644 --- a/arch/s390/include/asm/lowcore.h +++ b/arch/s390/include/asm/lowcore.h @@ -22,8 +22,13 @@ struct lowcore { __u32 ipl_parmblock_ptr; /* 0x0014 */ __u8 pad_0x0018[0x0080-0x0018]; /* 0x0018 */ __u32 ext_params; /* 0x0080 */ - __u16 ext_cpu_addr; /* 0x0084 */ - __u16 ext_int_code; /* 0x0086 */ + union { + struct { + __u16 ext_cpu_addr; /* 0x0084 */ + __u16 ext_int_code; /* 0x0086 */ + } __packed; + __u32 ext_int_code_addr; + } __packed; __u32 svc_int_code; /* 0x0088 */ __u16 pgm_ilc; /* 0x008c */ __u16 pgm_code; /* 0x008e */ diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c index 714269e10eec5..169258012530a 100644 --- a/arch/s390/kernel/irq.c +++ b/arch/s390/kernel/irq.c @@ -172,7 +172,7 @@ void noinstr do_ext_irq(struct pt_regs *regs) if (user_mode(regs)) update_timer_sys(); - memcpy(®s->int_code, &S390_lowcore.ext_cpu_addr, 4); + regs->int_code = S390_lowcore.ext_int_code_addr; regs->int_parm = S390_lowcore.ext_params; regs->int_parm_long = S390_lowcore.ext_params2; -- 2.30.2