From: David Gow davidgow@google.com
[ Upstream commit f4f03f299a56ce4d73c5431e0327b3b6cb55ebb9 ]
The syscall_handler_t type for x86_64 was defined as 'long (*)(void)', but always cast to 'long (*)(long, long, long, long, long, long)' before use. This now triggers a warning (see below).
Define syscall_handler_t as the latter instead, and remove the cast. This simplifies the code, and fixes the warning.
Warning: In file included from ../arch/um/include/asm/processor-generic.h:13 from ../arch/x86/um/asm/processor.h:41 from ../include/linux/rcupdate.h:30 from ../include/linux/rculist.h:11 from ../include/linux/pid.h:5 from ../include/linux/sched.h:14 from ../include/linux/ptrace.h:6 from ../arch/um/kernel/skas/syscall.c:7: ../arch/um/kernel/skas/syscall.c: In function ‘handle_syscall’: ../arch/x86/um/shared/sysdep/syscalls_64.h:18:11: warning: cast between incompatible function types from ‘long int (*)(void)’ to ‘long int (*)(long int, long int, long int, long int, long int, long int)’ [ -Wcast-function-type] 18 | (((long (*)(long, long, long, long, long, long)) \ | ^ ../arch/x86/um/asm/ptrace.h:36:62: note: in definition of macro ‘PT_REGS_SET_SYSCALL_RETURN’ 36 | #define PT_REGS_SET_SYSCALL_RETURN(r, res) (PT_REGS_AX(r) = (res)) | ^~~ ../arch/um/kernel/skas/syscall.c:46:33: note: in expansion of macro ‘EXECUTE_SYSCALL’ 46 | EXECUTE_SYSCALL(syscall, regs)); | ^~~~~~~~~~~~~~~
Signed-off-by: David Gow davidgow@google.com Signed-off-by: Richard Weinberger richard@nod.at Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/um/shared/sysdep/syscalls_64.h | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/x86/um/shared/sysdep/syscalls_64.h b/arch/x86/um/shared/sysdep/syscalls_64.h index 48d6cd12f8a5..b6b997225841 100644 --- a/arch/x86/um/shared/sysdep/syscalls_64.h +++ b/arch/x86/um/shared/sysdep/syscalls_64.h @@ -10,13 +10,12 @@ #include <linux/msg.h> #include <linux/shm.h>
-typedef long syscall_handler_t(void); +typedef long syscall_handler_t(long, long, long, long, long, long);
extern syscall_handler_t *sys_call_table[];
#define EXECUTE_SYSCALL(syscall, regs) \ - (((long (*)(long, long, long, long, long, long)) \ - (*sys_call_table[syscall]))(UPT_SYSCALL_ARG1(®s->regs), \ + (((*sys_call_table[syscall]))(UPT_SYSCALL_ARG1(®s->regs), \ UPT_SYSCALL_ARG2(®s->regs), \ UPT_SYSCALL_ARG3(®s->regs), \ UPT_SYSCALL_ARG4(®s->regs), \