From d99a043a9a506290a0aac6746a8e412df3dafbfb Mon Sep 17 00:00:00 2001
From: James Hogan <james.hogan@imgtec.com>
Date: Thu, 1 Sep 2016 17:30:13 +0100
Subject: [PATCH] MIPS: uprobes: Flush icache via kernel address
Update arch_uprobe_copy_ixol() to use the kmap_atomic() based kernel
address to flush the icache with flush_icache_range(), rather than the
user mapping. We have the kernel mapping available anyway and this
avoids having to switch to using the new __flush_icache_user_range() for
the sake of Enhanced Virtual Addressing (EVA) where flush_icache_range()
will become ineffective on user addresses.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14154/
Patchwork: https://patchwork.linux-mips.org/patch/14308/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
---
arch/mips/kernel/uprobes.c | 17 ++++++-----------
1 file changed, 6 insertions(+), 11 deletions(-)
diff --git a/arch/mips/kernel/uprobes.c b/arch/mips/kernel/uprobes.c
index 4c7c1558944a2..15ad17cb2b6e4 100644
--- a/arch/mips/kernel/uprobes.c
+++ b/arch/mips/kernel/uprobes.c
@@ -282,19 +282,14 @@ int __weak set_swbp(struct arch_uprobe *auprobe, struct mm_struct *mm,
void __weak arch_uprobe_copy_ixol(struct page *page, unsigned long vaddr,
void *src, unsigned long len)
{
- void *kaddr;
+ unsigned long kaddr, kstart;
/* Initialize the slot */
- kaddr = kmap_atomic(page);
- memcpy(kaddr + (vaddr & ~PAGE_MASK), src, len);
- kunmap_atomic(kaddr);
-
- /*
- * The MIPS version of flush_icache_range will operate safely on
- * user space addresses and more importantly, it doesn't require a
- * VMA argument.
- */
- flush_icache_range(vaddr, vaddr + len);
+ kaddr = (unsigned long)kmap_atomic(page);
+ kstart = kaddr + (vaddr & ~PAGE_MASK);
+ memcpy((void *)kstart, src, len);
+ flush_icache_range(kstart, kstart + len);
+ kunmap_atomic((void *)kaddr);
}
/**
--
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