Revert "kernel/debug: Mask KGDB NMI upon entry"

This reverts commit 5a14fead07bcf4e0acc877a8d9e1d1f40a441153.

No architectures ever implemented `enable_nmi` since the later patches
in the series adding it never landed. It's been a long time. Drop it.

NOTE: this is not a clean revert due to changes in the file in the
meantime.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20250129082535.3.I2254953cd852f31f354456689d68b2d910de3fbe@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index 14739952698b2f7f846bb7351f4740fd04503ff4..5eebbe7a3545674deb8f8647d6a11cda4f6a058f 100644 (file)
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -257,7 +257,6 @@ extern void kgdb_arch_late(void);
  * hardware breakpoints.
  * @correct_hw_break: Allow an architecture to specify how to correct the
  * hardware debug registers.
- * @enable_nmi: Manage NMI-triggered entry to KGDB
  */
 struct kgdb_arch {
        unsigned char           gdb_bpt_instr[BREAK_INSTR_SIZE];
@@ -270,8 +269,6 @@ struct kgdb_arch {
        void    (*disable_hw_break)(struct pt_regs *regs);
        void    (*remove_all_hw_break)(void);
        void    (*correct_hw_break)(void);
-
-       void    (*enable_nmi)(bool on);
 };
 
 /**

diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index ce1bb2301c061d9695d85f6508ed23380c4cb4ce..0b9495187fba6f22c5b1626dad82c184aaecd235 100644 (file)
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -837,10 +837,6 @@ kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
 {
        struct kgdb_state kgdb_var;
        struct kgdb_state *ks = &kgdb_var;
-       int ret = 0;
-
-       if (arch_kgdb_ops.enable_nmi)
-               arch_kgdb_ops.enable_nmi(0);
        /*
         * Avoid entering the debugger if we were triggered due to an oops
         * but panic_timeout indicates the system should automatically
@@ -858,15 +854,11 @@ kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
        ks->linux_regs          = regs;
 
        if (kgdb_reenter_check(ks))
-               goto out; /* Ouch, double exception ! */
+               return 0; /* Ouch, double exception ! */
        if (kgdb_info[ks->cpu].enter_kgdb != 0)
-               goto out;
+               return 0;
 
-       ret = kgdb_cpu_enter(ks, regs, DCPU_WANT_MASTER);
-out:
-       if (arch_kgdb_ops.enable_nmi)
-               arch_kgdb_ops.enable_nmi(1);
-       return ret;
+       return kgdb_cpu_enter(ks, regs, DCPU_WANT_MASTER);
 }
 NOKPROBE_SYMBOL(kgdb_handle_exception);