From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Brian Masney <bmasney@redhat.com>,
Juergen Gross <jgross@suse.com>,
Boris Ostrovsky <boris.ostrovsky@oracle.com>,
Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.4 07/24] x86/xen: dont unbind uninitialized lock_kicker_irq
Date: Tue, 1 Dec 2020 09:53:13 +0100 [thread overview]
Message-ID: <20201201084638.114361390@linuxfoundation.org> (raw)
In-Reply-To: <20201201084637.754785180@linuxfoundation.org>
From: Brian Masney <bmasney@redhat.com>
[ Upstream commit 65cae18882f943215d0505ddc7e70495877308e6 ]
When booting a hyperthreaded system with the kernel parameter
'mitigations=auto,nosmt', the following warning occurs:
WARNING: CPU: 0 PID: 1 at drivers/xen/events/events_base.c:1112 unbind_from_irqhandler+0x4e/0x60
...
Hardware name: Xen HVM domU, BIOS 4.2.amazon 08/24/2006
...
Call Trace:
xen_uninit_lock_cpu+0x28/0x62
xen_hvm_cpu_die+0x21/0x30
takedown_cpu+0x9c/0xe0
? trace_suspend_resume+0x60/0x60
cpuhp_invoke_callback+0x9a/0x530
_cpu_up+0x11a/0x130
cpu_up+0x7e/0xc0
bringup_nonboot_cpus+0x48/0x50
smp_init+0x26/0x79
kernel_init_freeable+0xea/0x229
? rest_init+0xaa/0xaa
kernel_init+0xa/0x106
ret_from_fork+0x35/0x40
The secondary CPUs are not activated with the nosmt mitigations and only
the primary thread on each CPU core is used. In this situation,
xen_hvm_smp_prepare_cpus(), and more importantly xen_init_lock_cpu(), is
not called, so the lock_kicker_irq is not initialized for the secondary
CPUs. Let's fix this by exiting early in xen_uninit_lock_cpu() if the
irq is not set to avoid the warning from above for each secondary CPU.
Signed-off-by: Brian Masney <bmasney@redhat.com>
Link: https://lore.kernel.org/r/20201107011119.631442-1-bmasney@redhat.com
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/x86/xen/spinlock.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c
index 85872a08994a1..e9fc0f7df0da8 100644
--- a/arch/x86/xen/spinlock.c
+++ b/arch/x86/xen/spinlock.c
@@ -301,10 +301,20 @@ void xen_init_lock_cpu(int cpu)
void xen_uninit_lock_cpu(int cpu)
{
+ int irq;
+
if (!xen_pvspin)
return;
- unbind_from_irqhandler(per_cpu(lock_kicker_irq, cpu), NULL);
+ /*
+ * When booting the kernel with 'mitigations=auto,nosmt', the secondary
+ * CPUs are not activated, and lock_kicker_irq is not initialized.
+ */
+ irq = per_cpu(lock_kicker_irq, cpu);
+ if (irq == -1)
+ return;
+
+ unbind_from_irqhandler(irq, NULL);
per_cpu(lock_kicker_irq, cpu) = -1;
kfree(per_cpu(irq_name, cpu));
per_cpu(irq_name, cpu) = NULL;
--
2.27.0
next prev parent reply other threads:[~2020-12-01 8:55 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-01 8:53 [PATCH 4.4 00/24] 4.4.247-rc1 review Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 01/24] btrfs: tree-checker: Enhance chunk checker to validate chunk profile Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 02/24] btrfs: inode: Verify inode mode to avoid NULL pointer dereference Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 03/24] KVM: x86: Fix split-irqchip vs interrupt injection window request Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 04/24] HID: cypress: Support Varmilo Keyboards media hotkeys Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 05/24] Input: i8042 - allow insmod to succeed on devices without an i8042 controller Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 06/24] HID: hid-sensor-hub: Fix issue with devices with no report ID Greg Kroah-Hartman
2020-12-01 8:53 ` Greg Kroah-Hartman [this message]
2020-12-01 8:53 ` [PATCH 4.4 08/24] proc: dont allow async path resolution of /proc/self components Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 09/24] dmaengine: pl330: _prep_dma_memcpy: Fix wrong burst size Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 10/24] scsi: libiscsi: Fix NOP race condition Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 11/24] scsi: target: iscsi: Fix cmd abort fabric stop race Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 12/24] scsi: ufs: Fix race between shutdown and runtime resume flow Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 13/24] bnxt_en: fix error return code in bnxt_init_board() Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 14/24] video: hyperv_fb: Fix the cache type when mapping the VRAM Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 15/24] bnxt_en: Release PCI regions when DMA mask setup fails during probe Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 16/24] IB/mthca: fix return value of error branch in mthca_init_cq() Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 17/24] nfc: s3fwrn5: use signed integer for parsing GPIO numbers Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 18/24] efivarfs: revert "fix memory leak in efivarfs_create()" Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 19/24] perf probe: Fix to die_entrypc() returns error correctly Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 20/24] USB: core: Change %pK for __user pointers to %px Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 21/24] x86/speculation: Fix prctl() when spectre_v2_user={seccomp,prctl},ibpb Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 22/24] USB: core: add endpoint-blacklist quirk Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 23/24] USB: core: Fix regression in Hercules audio card Greg Kroah-Hartman
2020-12-01 8:53 ` [PATCH 4.4 24/24] btrfs: fix lockdep splat when reading qgroup config on mount Greg Kroah-Hartman
2020-12-01 15:59 ` [PATCH 4.4 00/24] 4.4.247-rc1 review Pavel Machek
2020-12-01 21:38 ` Guenter Roeck
2020-12-02 6:17 ` Naresh Kamboju
2020-12-02 17:04 ` Shuah Khan
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