[Xen-devel] [PATCH v5 4/4] x86/smp: do not use scratch_cpumask when in interrupt or exception context

2020-02-26 Thread Roger Pau Monne
Using scratch_cpumask in send_IPI_mask is not safe in IRQ or exception context because it can nest, and hence send_IPI_mask could be overwriting another user scratch cpumask data when used in such contexts. Instead introduce a new cpumask to be used by send_IPI_mask, and disable interrupts while u

Re: [Xen-devel] [PATCH v5 4/4] x86/smp: do not use scratch_cpumask when in interrupt or exception context

2020-02-26 Thread Jan Beulich
On 26.02.2020 13:38, Roger Pau Monne wrote: > Using scratch_cpumask in send_IPI_mask is not safe in IRQ or exception > context because it can nest, and hence send_IPI_mask could be > overwriting another user scratch cpumask data when used in such > contexts. > > Instead introduce a new cpumask to

Re: [Xen-devel] [PATCH v5 4/4] x86/smp: do not use scratch_cpumask when in interrupt or exception context

2020-02-26 Thread Roger Pau Monné
On Wed, Feb 26, 2020 at 02:10:44PM +0100, Jan Beulich wrote: > On 26.02.2020 13:38, Roger Pau Monne wrote: > > Using scratch_cpumask in send_IPI_mask is not safe in IRQ or exception > > context because it can nest, and hence send_IPI_mask could be > > overwriting another user scratch cpumask data w