From: Alexandru Elisei <alexandru.elisei@arm.com>
To: kvm@vger.kernel.org
Cc: pbonzini@redhat.com, rkrcmar@redhat.com, drjones@redhat.com,
maz@kernel.org, andre.przywara@arm.com, vladimir.murzin@arm.com,
mark.rutland@arm.com
Subject: [kvm-unit-tests PATCH 17/18] arm/arm64: Invalidate TLB before enabling MMU
Date: Wed, 27 Nov 2019 14:24:09 +0000 [thread overview]
Message-ID: <20191127142410.1994-18-alexandru.elisei@arm.com> (raw)
In-Reply-To: <20191127142410.1994-1-alexandru.elisei@arm.com>
Let's invalidate the TLB before enabling the MMU, not after, so we don't
accidently use a stale TLB mapping. For arm, we add a TLBIALL operation,
which applies only to the PE that executed the instruction [1]. For arm64,
we already do that in asm_mmu_enable.
We now find ourselves in a situation where we issue an extra invalidation
after asm_mmu_enable returns. Remove this redundant call to tlb_flush_all.
[1] ARM DDI 0406C.d, section B3.10.6
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
---
lib/arm/mmu.c | 1 -
arm/cstart.S | 4 ++++
2 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/lib/arm/mmu.c b/lib/arm/mmu.c
index 773c764c4836..530d6b825398 100644
--- a/lib/arm/mmu.c
+++ b/lib/arm/mmu.c
@@ -59,7 +59,6 @@ void mmu_enable(pgd_t *pgtable)
struct thread_info *info = current_thread_info();
asm_mmu_enable(__pa(pgtable));
- flush_tlb_all();
info->pgtable = pgtable;
mmu_mark_enabled(info->cpu);
diff --git a/arm/cstart.S b/arm/cstart.S
index 3c2a3bcde61a..32b2b4f03098 100644
--- a/arm/cstart.S
+++ b/arm/cstart.S
@@ -161,6 +161,10 @@ halt:
.equ NMRR, 0xff000004 @ MAIR1 (from Linux kernel)
.globl asm_mmu_enable
asm_mmu_enable:
+ /* TLBIALL */
+ mcr p15, 0, r2, c8, c7, 0
+ dsb nsh
+
/* TTBCR */
ldr r2, =(TTBCR_EAE | \
TTBCR_SH0_SHARED | \
--
2.20.1
next prev parent reply other threads:[~2019-11-27 14:25 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-27 14:23 [kvm-unit-tests PATCH 00/18] Various fixes Alexandru Elisei
2019-11-27 14:23 ` [kvm-unit-tests PATCH 01/18] lib: arm/arm64: Remove unnecessary dcache maintenance operations Alexandru Elisei
2019-11-27 14:23 ` [kvm-unit-tests PATCH 02/18] lib: arm64: Remove barriers before TLB operations Alexandru Elisei
2019-11-27 14:23 ` [kvm-unit-tests PATCH 03/18] lib: Add WRITE_ONCE and READ_ONCE implementations in compiler.h Alexandru Elisei
2019-11-27 14:23 ` [kvm-unit-tests PATCH 04/18] lib: arm/arm64: Use WRITE_ONCE to update the translation tables Alexandru Elisei
2019-11-27 14:23 ` [kvm-unit-tests PATCH 05/18] lib: arm/arm64: Remove unused CPU_OFF parameter Alexandru Elisei
2019-11-27 14:23 ` [kvm-unit-tests PATCH 06/18] arm/arm64: psci: Don't run C code without stack or vectors Alexandru Elisei
2019-11-27 14:23 ` [kvm-unit-tests PATCH 07/18] lib: arm/arm64: Add missing include for alloc_page.h in pgtable.h Alexandru Elisei
2019-11-27 14:24 ` [kvm-unit-tests PATCH 08/18] lib: arm: Implement flush_tlb_all Alexandru Elisei
2019-11-27 14:24 ` [kvm-unit-tests PATCH 09/18] lib: arm/arm64: Teach mmu_clear_user about block mappings Alexandru Elisei
2019-11-27 14:24 ` [kvm-unit-tests PATCH 10/18] arm/arm64: selftest: Add prefetch abort test Alexandru Elisei
2019-11-27 18:47 ` Andrew Jones
2019-11-28 9:59 ` Alexandru Elisei
2019-11-28 16:56 ` Alexandru Elisei
2019-11-27 14:24 ` [kvm-unit-tests PATCH 11/18] arm64: timer: Write to ICENABLER to disable timer IRQ Alexandru Elisei
2019-11-27 14:24 ` [kvm-unit-tests PATCH 12/18] arm64: timer: EOIR the interrupt after masking the timer Alexandru Elisei
2019-11-27 14:24 ` [kvm-unit-tests PATCH 13/18] arm64: timer: Test behavior when timer disabled or masked Alexandru Elisei
2019-11-27 14:24 ` [kvm-unit-tests PATCH 14/18] lib: arm/arm64: Refuse to disable the MMU with non-identity stack pointer Alexandru Elisei
2019-11-27 14:24 ` [kvm-unit-tests PATCH 15/18] arm/arm64: Perform dcache clean + invalidate after turning MMU off Alexandru Elisei
2019-11-27 14:24 ` [kvm-unit-tests PATCH 16/18] arm: cstart64.S: Downgrade TLBI to non-shareable in asm_mmu_enable Alexandru Elisei
2019-11-27 14:24 ` Alexandru Elisei [this message]
2019-11-27 14:24 ` [kvm-unit-tests PATCH 18/18] arm: cstart64.S: Remove icache invalidation from asm_mmu_enable Alexandru Elisei
2019-11-27 14:41 ` Alexandru Elisei
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20191127142410.1994-18-alexandru.elisei@arm.com \
--to=alexandru.elisei@arm.com \
--cc=andre.przywara@arm.com \
--cc=drjones@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=maz@kernel.org \
--cc=pbonzini@redhat.com \
--cc=rkrcmar@redhat.com \
--cc=vladimir.murzin@arm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).