The type not being used in do_bug_frame() is suspicious. Apparently that's solely because the type uses a pointer-to-const parameter, when run_in_exception_handler() wants functions taking pointer-to-non- const. Drop the const, in turn requiring Arm's do_bug_frame() to also have its const dropped. This then brings that function also closer to the common one, with Arm's use of vaddr_t remaining as a difference.
Signed-off-by: Jan Beulich <[email protected]> --- This is an alternative proposal to https://lists.xen.org/archives/html/xen-devel/2023-12/msg01385.html, albeit without paving a road towards Andrew's desire of getting rid of show_execution_state_nonconst() again. Retaining (and propagating) the const would imply the need to cast away the const-ness somewhere on (at least) the path to invoking gdb stub code. Personally I'm averse to such casting away of const-ness ... --- a/xen/arch/arm/include/asm/traps.h +++ b/xen/arch/arm/include/asm/traps.h @@ -69,7 +69,7 @@ void do_cp(struct cpu_user_regs *regs, c void do_trap_smc(struct cpu_user_regs *regs, const union hsr hsr); void do_trap_hvc_smccc(struct cpu_user_regs *regs); -int do_bug_frame(const struct cpu_user_regs *regs, vaddr_t pc); +int do_bug_frame(struct cpu_user_regs *regs, vaddr_t pc); void noreturn do_unexpected_trap(const char *msg, const struct cpu_user_regs *regs); --- a/xen/arch/arm/traps.c +++ b/xen/arch/arm/traps.c @@ -1202,7 +1202,7 @@ void do_unexpected_trap(const char *msg, panic("CPU%d: Unexpected Trap: %s\n", smp_processor_id(), msg); } -int do_bug_frame(const struct cpu_user_regs *regs, vaddr_t pc) +int do_bug_frame(struct cpu_user_regs *regs, vaddr_t pc) { const struct bug_frame *bug = NULL; const char *prefix = "", *filename, *predicate; --- a/xen/common/bug.c +++ b/xen/common/bug.c @@ -63,14 +63,10 @@ int do_bug_frame(struct cpu_user_regs *r if ( id == BUGFRAME_run_fn ) { - void (*fn)(struct cpu_user_regs *) = bug_ptr(bug); + bug_fn_t *fn = bug_ptr(bug); fn(regs); - /* Re-enforce consistent types, because of the casts involved. */ - if ( false ) - run_in_exception_handler(fn); - return id; } --- a/xen/include/xen/bug.h +++ b/xen/include/xen/bug.h @@ -101,12 +101,11 @@ struct bug_frame { #endif struct cpu_user_regs; -typedef void bug_fn_t(const struct cpu_user_regs *regs); +typedef void bug_fn_t(struct cpu_user_regs *regs); #ifndef run_in_exception_handler -static void always_inline run_in_exception_handler( - void (*fn)(struct cpu_user_regs *regs)) +static void always_inline run_in_exception_handler(bug_fn_t *fn) { BUG_FRAME(BUGFRAME_run_fn, 0, fn, 0, NULL); }
