linux-kernel - [PATCH AUTOSEL 4.14 16/19] xen: remove stray preempt

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Date:   Thu,  9 Sep 2021 20:23:06 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Juergen Gross <jgross@...e.com>, Sasha Levin <sashal@...nel.org>,
        xen-devel@...ts.xenproject.org
Subject: [PATCH AUTOSEL 4.14 16/19] xen: remove stray preempt_disable() from PV AP startup code

From: Juergen Gross <jgross@...e.com>

[ Upstream commit 58e636039b512697554b579c2bb23774061877f5 ]

In cpu_bringup() there is a call of preempt_disable() without a paired
preempt_enable(). This is not needed as interrupts are off initially.
Additionally this will result in early boot messages like:

BUG: scheduling while atomic: swapper/1/0/0x00000002

Signed-off-by: Juergen Gross <jgross@...e.com>
Link: https://lore.kernel.org/r/20210825113158.11716-1-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@...e.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 arch/x86/xen/smp_pv.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c
index f779d2a5b04c..44468d6fa188 100644
--- a/arch/x86/xen/smp_pv.c
+++ b/arch/x86/xen/smp_pv.c
@@ -59,7 +59,6 @@ static void cpu_bringup(void)
 
 	cpu_init();
 	touch_softlockup_watchdog();
-	preempt_disable();
 
 	/* PVH runs in ring 0 and allows us to do native syscalls. Yay! */
 	if (!xen_feature(XENFEAT_supervisor_mode_kernel)) {
-- 
2.30.2