Radix MMU does not take SLB or TLB interrupts when accessing kernel
linear address. Remove this restriction for radix mode.
Signed-off-by: Nicholas Piggin <npig...@gmail.com>
arch/powerpc/kernel/setup_64.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index af23d4b576ec..7393bac3c7f4 100644
@@ -564,6 +564,9 @@ static __init u64 safe_stack_limit(void)
/* Other BookE, we assume the first GB is bolted */
return 1ul << 30;
+ if (early_radix_enabled())
+ return ULONG_MAX;
/* BookS, the first segment is bolted */
return 1UL << SID_SHIFT_1T;
@@ -578,7 +581,8 @@ void __init irqstack_early_init(void)
* Interrupt stacks must be in the first segment since we
- * cannot afford to take SLB misses on them.
+ * cannot afford to take SLB misses on them. They are not
+ * accessed in realmode.
softirq_ctx[i] = (struct thread_info *)
@@ -649,8 +653,9 @@ void __init emergency_stack_init(void)
* Since we use these as temporary stacks during secondary CPU
- * bringup, we need to get at them in real mode. This means they
- * must also be within the RMO region.
+ * bringup, machine check, system reset, and HMI, we need to get
+ * at them in real mode. This means they must also be within the RMO
+ * region.
* The IRQ stacks allocated elsewhere in this file are zeroed and
* initialized in kernel/irq.c. These are initialized here in order