Commit 0492747c authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Catalin Marinas
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arm64: KVM: Invoke compute_layout() before alternatives are applied 



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: default avatarJames Morse <james.morse@arm.com>
Acked-by: default avatarMarc Zyngier <maz@kernel.org>
Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent df325e05

arch/arm64/include/asm/kvm_mmu.h

+1 −0
Original line number Diff line number Diff line
@@ -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)

{

arch/arm64/kernel/smp.c

+4 −0
Original line number Diff line number Diff line
@@ -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>
@@ -408,6 +410,8 @@ 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)

arch/arm64/kvm/va_layout.c

+1 −7
Original line number Diff line number Diff line
@@ -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 alt_instr *alt, 


	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_instr *alt, 
		return;

	}



	if (!va_mask)

		compute_layout();



	/*

	 * Compute HYP VA by using the same computation as kern_hyp_va()

	 */