From: Will Deacon <will.deacon@arm.com>
To: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org, catalin.marinas@arm.com,
mark.rutland@arm.com, ard.biesheuvel@linaro.org,
sboyd@codeaurora.org, dave.hansen@linux.intel.com,
keescook@chromium.org, msalter@redhat.com, labbott@redhat.com,
tglx@linutronix.de, Will Deacon <will.deacon@arm.com>
Subject: [PATCH v3 19/20] arm64: mm: Introduce TTBR_ASID_MASK for getting at the ASID in the TTBR
Date: Wed, 6 Dec 2017 12:35:38 +0000 [thread overview]
Message-ID: <1512563739-25239-20-git-send-email-will.deacon@arm.com> (raw)
In-Reply-To: <1512563739-25239-1-git-send-email-will.deacon@arm.com>
There are now a handful of open-coded masks to extract the ASID from a
TTBR value, so introduce a TTBR_ASID_MASK and use that instead.
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
---
arch/arm64/include/asm/asm-uaccess.h | 3 ++-
arch/arm64/include/asm/mmu.h | 1 +
arch/arm64/include/asm/uaccess.h | 4 ++--
arch/arm64/kernel/entry.S | 2 +-
4 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/include/asm/asm-uaccess.h b/arch/arm64/include/asm/asm-uaccess.h
index 21b8cf304028..f4f234b6155e 100644
--- a/arch/arm64/include/asm/asm-uaccess.h
+++ b/arch/arm64/include/asm/asm-uaccess.h
@@ -4,6 +4,7 @@
#include <asm/alternative.h>
#include <asm/kernel-pgtable.h>
+#include <asm/mmu.h>
#include <asm/sysreg.h>
#include <asm/assembler.h>
@@ -17,7 +18,7 @@
msr ttbr0_el1, \tmp1 // set reserved TTBR0_EL1
isb
sub \tmp1, \tmp1, #SWAPPER_DIR_SIZE
- bic \tmp1, \tmp1, #(0xffff << 48)
+ bic \tmp1, \tmp1, #TTBR_ASID_MASK
msr ttbr1_el1, \tmp1 // set reserved ASID
isb
.endm
diff --git a/arch/arm64/include/asm/mmu.h b/arch/arm64/include/asm/mmu.h
index da6f12e40714..6f7bdb89817f 100644
--- a/arch/arm64/include/asm/mmu.h
+++ b/arch/arm64/include/asm/mmu.h
@@ -18,6 +18,7 @@
#define MMCF_AARCH32 0x1 /* mm context flag for AArch32 executables */
#define USER_ASID_FLAG (UL(1) << 48)
+#define TTBR_ASID_MASK (UL(0xffff) << 48)
#ifndef __ASSEMBLY__
diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h
index 750a3b76a01c..6eadf55ebaf0 100644
--- a/arch/arm64/include/asm/uaccess.h
+++ b/arch/arm64/include/asm/uaccess.h
@@ -112,7 +112,7 @@ static inline void __uaccess_ttbr0_disable(void)
write_sysreg(ttbr + SWAPPER_DIR_SIZE, ttbr0_el1);
isb();
/* Set reserved ASID */
- ttbr &= ~(0xffffUL << 48);
+ ttbr &= ~TTBR_ASID_MASK;
write_sysreg(ttbr, ttbr1_el1);
isb();
}
@@ -131,7 +131,7 @@ static inline void __uaccess_ttbr0_enable(void)
/* Restore active ASID */
ttbr1 = read_sysreg(ttbr1_el1);
- ttbr1 |= ttbr0 & (0xffffUL << 48);
+ ttbr1 |= ttbr0 & TTBR_ASID_MASK;
write_sysreg(ttbr1, ttbr1_el1);
isb();
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 5d51bdbb2131..3eabcb194c87 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -205,7 +205,7 @@ alternative_else_nop_endif
.if \el != 0
mrs x21, ttbr1_el1
- tst x21, #0xffff << 48 // Check for the reserved ASID
+ tst x21, #TTBR_ASID_MASK // Check for the reserved ASID
orr x23, x23, #PSR_PAN_BIT // Set the emulated PAN in the saved SPSR
b.eq 1f // TTBR0 access already disabled
and x23, x23, #~PSR_PAN_BIT // Clear the emulated PAN in the saved SPSR
--
2.1.4
next prev parent reply other threads:[~2017-12-06 12:37 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-12-06 12:35 [PATCH v3 00/20] arm64: Unmap the kernel whilst running in userspace (KPTI) Will Deacon
2017-12-06 12:35 ` [PATCH v3 01/20] arm64: mm: Use non-global mappings for kernel space Will Deacon
2017-12-06 12:35 ` [PATCH v3 02/20] arm64: mm: Temporarily disable ARM64_SW_TTBR0_PAN Will Deacon
2017-12-06 12:35 ` [PATCH v3 03/20] arm64: mm: Move ASID from TTBR0 to TTBR1 Will Deacon
2017-12-06 12:35 ` [PATCH v3 04/20] arm64: mm: Remove pre_ttbr0_update_workaround for Falkor erratum #E1003 Will Deacon
2017-12-06 12:35 ` [PATCH v3 05/20] arm64: mm: Rename post_ttbr0_update_workaround Will Deacon
2017-12-06 12:35 ` [PATCH v3 06/20] arm64: mm: Fix and re-enable ARM64_SW_TTBR0_PAN Will Deacon
2018-01-17 2:58 ` Yisheng Xie
2017-12-06 12:35 ` [PATCH v3 07/20] arm64: mm: Allocate ASIDs in pairs Will Deacon
2017-12-06 12:35 ` [PATCH v3 08/20] arm64: mm: Add arm64_kernel_unmapped_at_el0 helper Will Deacon
2017-12-06 12:35 ` [PATCH v3 09/20] arm64: mm: Invalidate both kernel and user ASIDs when performing TLBI Will Deacon
2017-12-06 12:35 ` [PATCH v3 10/20] arm64: entry: Add exception trampoline page for exceptions from EL0 Will Deacon
2017-12-06 12:35 ` [PATCH v3 11/20] arm64: mm: Map entry trampoline into trampoline and kernel page tables Will Deacon
2017-12-06 14:32 ` Mark Rutland
2018-01-23 8:28 ` Yisheng Xie
2018-01-23 10:04 ` Will Deacon
2018-01-23 10:43 ` Yisheng Xie
2017-12-06 12:35 ` [PATCH v3 12/20] arm64: entry: Explicitly pass exception level to kernel_ventry macro Will Deacon
2017-12-06 12:35 ` [PATCH v3 13/20] arm64: entry: Hook up entry trampoline to exception vectors Will Deacon
2017-12-06 12:35 ` [PATCH v3 14/20] arm64: erratum: Work around Falkor erratum #E1003 in trampoline code Will Deacon
2017-12-06 12:35 ` [PATCH v3 15/20] arm64: tls: Avoid unconditional zeroing of tpidrro_el0 for native tasks Will Deacon
2017-12-06 12:35 ` [PATCH v3 16/20] arm64: entry: Add fake CPU feature for unmapping the kernel at EL0 Will Deacon
2017-12-06 14:11 ` Mark Rutland
2017-12-06 12:35 ` [PATCH v3 17/20] arm64: Kconfig: Add CONFIG_UNMAP_KERNEL_AT_EL0 Will Deacon
2017-12-06 12:35 ` [PATCH v3 18/20] perf: arm_spe: Fail device probe when arm64_kernel_unmapped_at_el0() Will Deacon
2017-12-06 13:34 ` Mark Rutland
2017-12-06 12:35 ` Will Deacon [this message]
2017-12-06 14:12 ` [PATCH v3 19/20] arm64: mm: Introduce TTBR_ASID_MASK for getting at the ASID in the TTBR Mark Rutland
2017-12-06 12:35 ` [PATCH v3 20/20] arm64: kaslr: Put kernel vectors address in separate data page Will Deacon
2017-12-06 12:59 ` Ard Biesheuvel
2017-12-06 13:27 ` Will Deacon
2017-12-06 14:03 ` Ard Biesheuvel
2017-12-08 0:40 ` [PATCH v3 00/20] arm64: Unmap the kernel whilst running in userspace (KPTI) Laura Abbott
2017-12-11 13:23 ` Will Deacon
2017-12-11 17:59 ` Catalin Marinas
2018-01-04 5:17 ` Florian Fainelli
2018-01-04 6:50 ` Greg Kroah-Hartman
2018-01-04 18:23 ` Florian Fainelli
2018-01-04 23:27 ` Russell King - ARM Linux
2018-01-05 16:06 ` Greg Kroah-Hartman
2018-01-05 16:12 ` Ard Biesheuvel
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