From 80f7fdb1c7f0f9266421f823964fd1962681f6ce Mon Sep 17 00:00:00 2001 From: =?utf8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= Date: Thu, 2 Apr 2015 20:44:23 +0200 Subject: [PATCH] x86: vdso: fix pvclock races with task migration MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit If we were migrated right after __getcpu, but before reading the migration_count, we wouldn't notice that we read TSC of a different VCPU, nor that KVM's bug made pvti invalid, as only migration_count on source VCPU is increased. Change vdso instead of updating migration_count on destination. Cc: stable@vger.kernel.org Signed-off-by: Radim Krčmář Fixes: 0a4e6be9ca17 ("x86: kvm: Revert "remove sched notifier for cross-cpu migrations"") Message-Id: <1428000263-11892-1-git-send-email-rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini --- Reading git-format-patch failed