linux-kernel - [PATCH 3/3] irq: Comment on the use of inline stack for ksoftirqd

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-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 19 Sep 2013 14:51:07 -0500
From:	Frederic Weisbecker <fweisbec@...il.com>
To:	Thomas Gleixner <tglx@...utronix.de>
Cc:	LKML <linux-kernel@...r.kernel.org>,
	Frederic Weisbecker <fweisbec@...il.com>,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	Paul Mackerras <paulus@....ibm.com>,
	Ingo Molnar <mingo@...nel.org>,
	Peter Zijlstra <peterz@...radead.org>,
	"H. Peter Anvin" <hpa@...or.com>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	James Hogan <james.hogan@...tec.com>,
	"James E.J. Bottomley" <jejb@...isc-linux.org>,
	Helge Deller <deller@....de>,
	Martin Schwidefsky <schwidefsky@...ibm.com>,
	Heiko Carstens <heiko.carstens@...ibm.com>,
	"David S. Miller" <davem@...emloft.net>,
	Andrew Morton <akpm@...ux-foundation.org>
Subject: [PATCH 3/3] irq: Comment on the use of inline stack for ksoftirqd

Ksoftirqd shouldn't need softirq stack since it's executing
in a kernel thread with a callstack that is only beginning at
this stage.

Lets comment about that for clarity.

Signed-off-by: Frederic Weisbecker <fweisbec@...il.com>
Cc: Benjamin Herrenschmidt <benh@...nel.crashing.org>
Cc: Paul Mackerras <paulus@....ibm.com>
Cc: Ingo Molnar <mingo@...nel.org>
Cc: Thomas Gleixner <tglx@...utronix.de>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: H. Peter Anvin <hpa@...or.com>
Cc: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Paul Mackerras <paulus@....ibm.com>
Cc: James Hogan <james.hogan@...tec.com>
Cc: James E.J. Bottomley <jejb@...isc-linux.org>
Cc: Helge Deller <deller@....de>
Cc: Martin Schwidefsky <schwidefsky@...ibm.com>
Cc: Heiko Carstens <heiko.carstens@...ibm.com>
Cc: David S. Miller <davem@...emloft.net>
Cc: Andrew Morton <akpm@...ux-foundation.org>
---
 kernel/softirq.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/kernel/softirq.c b/kernel/softirq.c
index 8c8f08b..1b0f48e 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -759,6 +759,10 @@ static void run_ksoftirqd(unsigned int cpu)
 {
 	local_irq_disable();
 	if (local_softirq_pending()) {
+		/*
+		 * Execute softirq on inline stack, as we are not deep in
+		 * the task stack here.
+		 */
 		__do_softirq();
 		rcu_note_context_switch(cpu);
 		local_irq_enable();
-- 
1.8.3.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/