lkml.org 
[lkml]   [2018]   [Mar]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] arm64: tlbflush: avoid writing RES0 bits
Date
Bits [47:44] of the TLBI register operand are RES0 for instructions that
require a VA, per the ARM ARM spec, so TLBI operations should avoid writing
non-zero values to these bits.

Signed-off-by: Philip Elcan <pelcan@codeaurora.org>
---
arch/arm64/include/asm/tlbflush.h | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h
index 9e82dd7..dbd22a9 100644
--- a/arch/arm64/include/asm/tlbflush.h
+++ b/arch/arm64/include/asm/tlbflush.h
@@ -60,6 +60,9 @@
__tlbi(op, (arg) | USER_ASID_FLAG); \
} while (0)

+/* This macro masks out RES0 bits in the TLBI operand */
+#define __TLBI_VADDR(addr) (addr & ~GENMASK_ULL(47, 44))
+
/*
* TLB Management
* ==============
@@ -128,7 +131,8 @@ static inline void flush_tlb_mm(struct mm_struct *mm)
static inline void flush_tlb_page(struct vm_area_struct *vma,
unsigned long uaddr)
{
- unsigned long addr = uaddr >> 12 | (ASID(vma->vm_mm) << 48);
+ unsigned long addr = __TLBI_VADDR(uaddr >> 12) |
+ (ASID(vma->vm_mm) << 48);

dsb(ishst);
__tlbi(vale1is, addr);
@@ -154,8 +158,8 @@ static inline void __flush_tlb_range(struct vm_area_struct *vma,
return;
}

- start = asid | (start >> 12);
- end = asid | (end >> 12);
+ start = asid | __TLBI_VADDR(start >> 12);
+ end = asid | __TLBI_VADDR(end >> 12);

dsb(ishst);
for (addr = start; addr < end; addr += 1 << (PAGE_SHIFT - 12)) {
@@ -185,8 +189,8 @@ static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end
return;
}

- start >>= 12;
- end >>= 12;
+ start = __TLBI_VADDR(start >> 12);
+ end = __TLBI_VADDR(end >> 12);

dsb(ishst);
for (addr = start; addr < end; addr += 1 << (PAGE_SHIFT - 12))
@@ -202,7 +206,7 @@ static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end
static inline void __flush_tlb_pgtable(struct mm_struct *mm,
unsigned long uaddr)
{
- unsigned long addr = uaddr >> 12 | (ASID(mm) << 48);
+ unsigned long addr = __TLBI_VADDR(uaddr >> 12) | (ASID(mm) << 48);

__tlbi(vae1is, addr);
__tlbi_user(vae1is, addr);
--
Qualcomm Datacenter Technologies as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.
\
 
 \ /
  Last update: 2018-03-21 22:04    [W:0.236 / U:0.136 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site