From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Thu, 28 Nov 2019 20:58:05 +0100
Subject: arm64: KVM: Invoke compute_layout() before alternatives are applied
Patch-mainline: v5.5-rc1
Git-commit: 0492747c72a3db0425a234abafb763c5b28c845d
References: bsc#1162702
compute_layout() is invoked as part of an alternative fixup under
stop_machine(). This function invokes get_random_long() which acquires a
sleeping lock on -RT which can not be acquired in this context.
Rename compute_layout() to kvm_compute_layout() and invoke it before
stop_machine() applies the alternatives. Add a __init prefix to
kvm_compute_layout() because the caller has it, too (and so the code can be
discarded after boot).
Reviewed-by: James Morse <james.morse@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Daniel Wagner <dwagner@suse.de>
---
arch/arm64/include/asm/kvm_mmu.h | 1 +
arch/arm64/kernel/smp.c | 4 ++++
arch/arm64/kvm/va_layout.c | 8 +-------
3 files changed, 6 insertions(+), 7 deletions(-)
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -91,6 +91,7 @@ alternative_cb_end
void kvm_update_va_mask(struct alt_instr *alt,
__le32 *origptr, __le32 *updptr, int nr_inst);
+void kvm_compute_layout(void);
static inline unsigned long __kern_hyp_va(unsigned long v)
{
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -31,6 +31,7 @@
#include <linux/of.h>
#include <linux/irq_work.h>
#include <linux/kexec.h>
+#include <linux/kvm_host.h>
#include <asm/alternative.h>
#include <asm/atomic.h>
@@ -39,6 +40,7 @@
#include <asm/cputype.h>
#include <asm/cpu_ops.h>
#include <asm/daifflags.h>
+#include <asm/kvm_mmu.h>
#include <asm/mmu_context.h>
#include <asm/numa.h>
#include <asm/pgtable.h>
@@ -406,6 +408,8 @@ static void __init hyp_mode_check(void)
"CPU: CPUs started in inconsistent modes");
else
pr_info("CPU: All CPU(s) started at EL1\n");
+ if (IS_ENABLED(CONFIG_KVM_ARM_HOST))
+ kvm_compute_layout();
}
void __init smp_cpus_done(unsigned int max_cpus)
--- a/arch/arm64/kvm/va_layout.c
+++ b/arch/arm64/kvm/va_layout.c
@@ -22,7 +22,7 @@ static u8 tag_lsb;
static u64 tag_val;
static u64 va_mask;
-static void compute_layout(void)
+__init void kvm_compute_layout(void)
{
phys_addr_t idmap_addr = __pa_symbol(__hyp_idmap_text_start);
u64 hyp_va_msb;
@@ -110,9 +110,6 @@ void __init kvm_update_va_mask(struct al
BUG_ON(nr_inst != 5);
- if (!has_vhe() && !va_mask)
- compute_layout();
-
for (i = 0; i < nr_inst; i++) {
u32 rd, rn, insn, oinsn;
@@ -156,9 +153,6 @@ void kvm_patch_vector_branch(struct alt_
return;
}
- if (!va_mask)
- compute_layout();
-
/*
* Compute HYP VA by using the same computation as kern_hyp_va()
*/