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(&regs->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 <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This commit is contained in:
Sven Schnelle 2021-05-05 22:01:11 +02:00 committed by Vasily Gorbik
parent 17e89e1340
commit 6c6a07fc7c
2 changed files with 8 additions and 3 deletions

View File

@ -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 */

View File

@ -172,7 +172,7 @@ void noinstr do_ext_irq(struct pt_regs *regs)
if (user_mode(regs))
update_timer_sys();
memcpy(&regs->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;