On 12/12/2018 16:47, Julien Thierry wrote:
> When using VHE, the host needs to clear HCR_EL2.TGE bit in order
> to interract with guest TLBs, switching from EL2&0 translation regime
> to EL1&0.
>
> However, some non-maskable asynchronous event could happen while TGE is
> cleared like SDEI. Because of this address translation operations
> relying on EL2&0 translation regime could fail (tlb invalidation,
> userspace access, ...).
>
> Fix this by properly setting HCR_EL2.TGE when entering NMI context and
> clear it if necessary when returning to the interrupted context.
>
> Signed-off-by: Julien Thierry <julien.thierry@xxxxxxx>
> Suggested-by: Marc Zyngier <marc.zyngier@xxxxxxx>
> Cc: Arnd Bergmann <arnd@xxxxxxxx>
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Will Deacon <will.deacon@xxxxxxx>
> Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
> Cc: James Morse <james.morse@xxxxxxx>
> Cc: linux-arch@xxxxxxxxxxxxxxx
> Cc: stable@xxxxxxxxxxxxxxx
> ---
> arch/arm64/include/asm/hardirq.h | 28 ++++++++++++++++++++++++++++
> arch/arm64/kernel/irq.c | 3 +++
> include/asm-generic/hardirq.h | 3 +++
> include/linux/hardirq.h | 2 ++
> 4 files changed, 36 insertions(+)
>
> diff --git a/include/asm-generic/hardirq.h b/include/asm-generic/hardirq.h
> index d14214d..c33b53f20 100644
> --- a/include/asm-generic/hardirq.h
> +++ b/include/asm-generic/hardirq.h
> @@ -12,6 +12,9 @@
> #include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
> #include <linux/irq.h>
>
> +#define arch_nmi_enter() do { } while (0)
> +#define arch_nmi_exit() do { } while (0)
> +
As spotted by the build bot, this needs to go in include/linux/hardirq.h
under a #ifndef arch_nmi_enter.
> #ifndef ack_bad_irq
> static inline void ack_bad_irq(unsigned int irq)
> {
> diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h
> index 0fbbcdf..776a60f 100644
> --- a/include/linux/hardirq.h
> +++ b/include/linux/hardirq.h
> @@ -62,6 +62,7 @@ static inline void rcu_nmi_exit(void)
>
> #define nmi_enter() \
> do { \
> + arch_nmi_enter(); \
> printk_nmi_enter(); \
> lockdep_off(); \
> ftrace_nmi_enter(); \
> @@ -80,6 +81,7 @@ static inline void rcu_nmi_exit(void)
> ftrace_nmi_exit(); \
> lockdep_on(); \
> printk_nmi_exit(); \
> + arch_nmi_exit(); \
> } while (0)
>
> #endif /* LINUX_HARDIRQ_H */
>
--
Julien Thierry
