| Message ID | 20190128115026.3336-2-julien.grall@arm.com |
|---|---|
| State | New |
| Headers | show |
| Series | xen/arm: Workaround for Cortex-A76 erratum 1165522 | expand |
diff --git a/xen/arch/arm/traps.c b/xen/arch/arm/traps.c index 221c762ada..64a78d83a5 100644 --- a/xen/arch/arm/traps.c +++ b/xen/arch/arm/traps.c @@ -157,8 +157,12 @@ void init_traps(void) WRITE_SYSREG((HCPTR_CP_MASK & ~(HCPTR_CP(10) | HCPTR_CP(11))) | HCPTR_TTA, CPTR_EL2); - /* Setup hypervisor traps */ - WRITE_SYSREG(get_default_hcr_flags(), HCR_EL2); + /* + * Configure HCR_EL2 with the bare minimum to run Xen until a guest + * is scheduled. {A,I,F}MO bits are set to allow EL2 receiving + * interrupts. + */ + WRITE_SYSREG(HCR_AMO | HCR_FMO | HCR_IMO, HCR_EL2); isb(); }
Only {A,F,I}MO are necessary to receive interrupts until a guest vCPU is loaded. The rest have no effect on Xen and it is better to avoid setting them. Signed-off-by: Julien Grall <julien.grall@arm.com> Reviewed-by: Andrii Anisov <andrii_anisov@epam.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> --- Changes in v2: - Fix typo - Add Andrii's and Stefano's reviewed-by --- xen/arch/arm/traps.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)