Commit e8a69f12 authored by Boris Ostrovsky's avatar Boris Ostrovsky Committed by Thomas Gleixner
Browse files

x86/xen: Allow to retry if cpu_initialize_context() failed. 



If memory allocation in cpu_initialize_context() fails then it will
bring up the VCPU and leave with the corresponding CPU bit set in
xen_cpu_initialized_map.

The following (presumably successful) CPU bring up will BUG in
xen_pv_cpu_up() because nothing for that VCPU would be initialized.

Clear the CPU bits, that were set in cpu_initialize_context() in case
the memory allocation fails.

[ bigeasy: Creating a patch from Boris' email. ]

Signed-off-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220209080214.1439408-2-bigeasy@linutronix.de
parent ce522ba9

arch/x86/xen/smp_pv.c

+4 −1
Original line number Diff line number Diff line
@@ -260,8 +260,11 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle) 
		return 0;



	ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);

	if (ctxt == NULL)

	if (ctxt == NULL) {

		cpumask_clear_cpu(cpu, xen_cpu_initialized_map);

		cpumask_clear_cpu(cpu, cpu_callout_mask);

		return -ENOMEM;

	}



	gdt = get_cpu_gdt_rw(cpu);