lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <20250220225302.195282-1-hamzamahfooz@linux.microsoft.com>
Date: Thu, 20 Feb 2025 17:53:00 -0500
From: Hamza Mahfooz <hamzamahfooz@...ux.microsoft.com>
To: linux-kernel@...r.kernel.org
Cc: Wei Liu <wei.liu@...nel.org>,
	linux-hyperv@...r.kernel.org,
	Dexuan Cui <decui@...rosoft.com>,
	Haiyang Zhang <haiyangz@...rosoft.com>,
	Hamza Mahfooz <hamzamahfooz@...ux.microsoft.com>,
	Petr Mladek <pmladek@...e.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Jani Nikula <jani.nikula@...el.com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	John Ogness <john.ogness@...utronix.de>,
	Baoquan He <bhe@...hat.com>,
	Joel Granados <joel.granados@...nel.org>,
	Jocelyn Falempe <jfalempe@...hat.com>,
	Ryo Takakura <takakura@...inux.co.jp>
Subject: [PATCH RFC] panic: call panic handlers before panic_other_cpus_shutdown()

Since, the panic handlers may require certain cpus to be online to panic
gracefully, we should call them before turning off SMP. Without this
re-ordering, on Hyper-V hv_panic_vmbus_unload() times out, because the
vmbus channel is bound to VMBUS_CONNECT_CPU and unless the crashing cpu
is the same as VMBUS_CONNECT_CPU, VMBUS_CONNECT_CPU will be offlined by
crash_smp_send_stop() before the vmbus channel can be deconstructed.

Signed-off-by: Hamza Mahfooz <hamzamahfooz@...ux.microsoft.com>
---
 kernel/panic.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/panic.c b/kernel/panic.c
index fbc59b3b64d0..9712a46dfe27 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -372,8 +372,6 @@ void panic(const char *fmt, ...)
 	if (!_crash_kexec_post_notifiers)
 		__crash_kexec(NULL);
 
-	panic_other_cpus_shutdown(_crash_kexec_post_notifiers);
-
 	printk_legacy_allow_panic_sync();
 
 	/*
@@ -382,6 +380,8 @@ void panic(const char *fmt, ...)
 	 */
 	atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
 
+	panic_other_cpus_shutdown(_crash_kexec_post_notifiers);
+
 	panic_print_sys_info(false);
 
 	kmsg_dump_desc(KMSG_DUMP_PANIC, buf);
-- 
2.47.1


Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ