+ panic-only-warn-about-deprecated-panic_print-on-write-access.patch added to mm-hotfixes-unstable branch

+ panic-only-warn-about-deprecated-panic_print-on-write-access.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: panic: only warn about deprecated panic_print on write access
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     panic-only-warn-about-deprecated-panic_print-on-write-access.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/panic-only-warn-about-deprecated-panic_print-on-write-access.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Gal Pressman <gal@nvidia.com>
Subject: panic: only warn about deprecated panic_print on write access
Date: Tue, 6 Jan 2026 18:33:21 +0200

The panic_print_deprecated() warning is being triggered on both read and
write operations to the panic_print parameter.

This causes spurious warnings when users run 'sysctl -a' to list all
sysctl values, since that command reads /proc/sys/kernel/panic_print and
triggers the deprecation notice.

Modify the handlers to only emit the deprecation warning when the
parameter is actually being set:

 - sysctl_panic_print_handler(): check 'write' flag before warning.
 - panic_print_get(): remove the deprecation call entirely.

This way, users are only warned when they actively try to use the
deprecated parameter, not when passively querying system state.

Link: https://lkml.kernel.org/r/20260106163321.83586-1-gal@nvidia.com
Fixes: ee13240cd78b ("panic: add note that panic_print sysctl interface is deprecated")
Fixes: 2683df6539cb ("panic: add note that 'panic_print' parameter is deprecated")
Signed-off-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Reviewed-by: Nimrod Oren <noren@nvidia.com>
Cc: Feng Tang <feng.tang@linux.alibaba.com>
Cc: Joel Granados <joel.granados@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/panic.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/kernel/panic.c~panic-only-warn-about-deprecated-panic_print-on-write-access
+++ a/kernel/panic.c
@@ -131,7 +131,8 @@ static int proc_taint(const struct ctl_t
 static int sysctl_panic_print_handler(const struct ctl_table *table, int write,
 			   void *buffer, size_t *lenp, loff_t *ppos)
 {
-	panic_print_deprecated();
+	if (write)
+		panic_print_deprecated();
 	return proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
 }
 
@@ -1014,7 +1015,6 @@ static int panic_print_set(const char *v
 
 static int panic_print_get(char *val, const struct kernel_param *kp)
 {
-	panic_print_deprecated();
 	return  param_get_ulong(val, kp);
 }
 
_

Patches currently in -mm which might be from gal@nvidia.com are

panic-only-warn-about-deprecated-panic_print-on-write-access.patch