4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Stefano Stabellini sstabellini@kernel.org
[ Upstream commit 7bf9a6b46549852a37e6d07e52c601c3c706b562 ]
xen_vcpu_info is a percpu area than needs to be mapped by Xen. Currently, it could cross a page boundary resulting in Xen being unable to map it:
[ 0.567318] kernel BUG at arch/arm64/xen/../../arm/xen/enlighten.c:164! [ 0.574002] Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Fix the issue by using __alloc_percpu and requesting alignment for the memory allocation.
Signed-off-by: Stefano Stabellini stefano.stabellini@amd.com
Link: https://lore.kernel.org/r/alpine.DEB.2.22.394.2311221501340.2053963@ubuntu-l... Fixes: 24d5373dda7c ("arm/xen: Use alloc_percpu rather than __alloc_percpu") Reviewed-by: Juergen Gross jgross@suse.com Signed-off-by: Juergen Gross jgross@suse.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm/xen/enlighten.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index 32aa108b2b7cd..7a18bdf32ecc2 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -376,7 +376,8 @@ static int __init xen_guest_init(void) * for secondary CPUs as they are brought up. * For uniformity we use VCPUOP_register_vcpu_info even on cpu0. */ - xen_vcpu_info = alloc_percpu(struct vcpu_info); + xen_vcpu_info = __alloc_percpu(sizeof(struct vcpu_info), + 1 << fls(sizeof(struct vcpu_info) - 1)); if (xen_vcpu_info == NULL) return -ENOMEM;