arm64: Fix HCR.TGE status for NMI contexts

When using VHE, the host needs to clear HCR_EL2.TGE bit in order
to interact 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@arm.com>
Suggested-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Julien Thierry 2019-01-31 14:58:39 +00:00 committed by Catalin Marinas
parent e26a433147
commit 5870970b9a
3 changed files with 41 additions and 0 deletions

View File

@ -17,8 +17,12 @@
#define __ASM_HARDIRQ_H
#include <linux/cache.h>
#include <linux/percpu.h>
#include <linux/threads.h>
#include <asm/barrier.h>
#include <asm/irq.h>
#include <asm/kvm_arm.h>
#include <asm/sysreg.h>
#define NR_IPI 7
@ -37,6 +41,33 @@ u64 smp_irq_stat_cpu(unsigned int cpu);
#define __ARCH_IRQ_EXIT_IRQS_DISABLED 1
struct nmi_ctx {
u64 hcr;
};
DECLARE_PER_CPU(struct nmi_ctx, nmi_contexts);
#define arch_nmi_enter() \
do { \
if (is_kernel_in_hyp_mode()) { \
struct nmi_ctx *nmi_ctx = this_cpu_ptr(&nmi_contexts); \
nmi_ctx->hcr = read_sysreg(hcr_el2); \
if (!(nmi_ctx->hcr & HCR_TGE)) { \
write_sysreg(nmi_ctx->hcr | HCR_TGE, hcr_el2); \
isb(); \
} \
} \
} while (0)
#define arch_nmi_exit() \
do { \
if (is_kernel_in_hyp_mode()) { \
struct nmi_ctx *nmi_ctx = this_cpu_ptr(&nmi_contexts); \
if (!(nmi_ctx->hcr & HCR_TGE)) \
write_sysreg(nmi_ctx->hcr, hcr_el2); \
} \
} while (0)
static inline void ack_bad_irq(unsigned int irq)
{
extern unsigned long irq_err_count;

View File

@ -33,6 +33,9 @@
unsigned long irq_err_count;
/* Only access this in an NMI enter/exit */
DEFINE_PER_CPU(struct nmi_ctx, nmi_contexts);
DEFINE_PER_CPU(unsigned long *, irq_stack_ptr);
int arch_show_interrupts(struct seq_file *p, int prec)

View File

@ -60,8 +60,14 @@ extern void irq_enter(void);
*/
extern void irq_exit(void);
#ifndef arch_nmi_enter
#define arch_nmi_enter() do { } while (0)
#define arch_nmi_exit() do { } while (0)
#endif
#define nmi_enter() \
do { \
arch_nmi_enter(); \
printk_nmi_enter(); \
lockdep_off(); \
ftrace_nmi_enter(); \
@ -80,6 +86,7 @@ extern void irq_exit(void);
ftrace_nmi_exit(); \
lockdep_on(); \
printk_nmi_exit(); \
arch_nmi_exit(); \
} while (0)
#endif /* LINUX_HARDIRQ_H */