LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Kefeng Wang <wangkefeng.wang@huawei.com>
To: Russell King <linux@armlinux.org.uk>,
	Alexander Potapenko <glider@google.com>,
	Marco Elver <elver@google.com>,
	Dmitry Vyukov <dvyukov@google.com>,
	<linux-arm-kernel@lists.infradead.org>,
	<linux-kernel@vger.kernel.org>, <kasan-dev@googlegroups.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Kefeng Wang <wangkefeng.wang@huawei.com>
Subject: [PATCH 2/4] ARM: mm: Provide is_write_fault()
Date: Wed, 25 Aug 2021 17:21:14 +0800	[thread overview]
Message-ID: <20210825092116.149975-3-wangkefeng.wang@huawei.com> (raw)
In-Reply-To: <20210825092116.149975-1-wangkefeng.wang@huawei.com>

The function will check whether the fault is caused by a write access.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
 arch/arm/mm/fault.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index bc8779d54a64..f7ab6dabe89f 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -207,6 +207,11 @@ static inline bool is_permission_fault(unsigned int fsr)
 	return false;
 }
 
+static inline bool is_write_fault(unsigned int fsr)
+{
+	return (fsr & FSR_WRITE) && !(fsr & FSR_CM);
+}
+
 static vm_fault_t __kprobes
 __do_page_fault(struct mm_struct *mm, unsigned long addr, unsigned int flags,
 		unsigned long vma_flags, struct pt_regs *regs)
@@ -261,7 +266,7 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 	if (user_mode(regs))
 		flags |= FAULT_FLAG_USER;
 
-	if ((fsr & FSR_WRITE) && !(fsr & FSR_CM)) {
+	if (is_write_fault(fsr)) {
 		flags |= FAULT_FLAG_WRITE;
 		vm_flags = VM_WRITE;
 	}
-- 
2.26.2


  parent reply	other threads:[~2021-08-25  9:17 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-25  9:21 [PATCH 0/4] ARM: Support KFENCE feature Kefeng Wang
2021-08-25  9:21 ` [PATCH 1/4] ARM: mm: Provide set_memory_valid() Kefeng Wang
2021-08-25  9:21 ` Kefeng Wang [this message]
2021-08-25  9:21 ` [PATCH 3/4] ARM: Support KFENCE for ARM Kefeng Wang
2021-08-25 13:18   ` ownia
2021-08-25 14:31     ` Kefeng Wang
2021-08-25  9:21 ` [PATCH 4/4] mm: kfence: Only load kfence_test when kfence is enabled Kefeng Wang
2021-08-25  9:31   ` Alexander Potapenko
2021-08-25  9:54     ` Marco Elver
2021-08-25  9:55     ` Kefeng Wang
2021-08-25  9:59       ` Marco Elver
2021-08-25 10:14 ` [PATCH 0/4] ARM: Support KFENCE feature Marco Elver
2021-08-25 10:57   ` Marco Elver
2021-08-25 14:15     ` Kefeng Wang
2021-08-25 14:28     ` Kefeng Wang

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=20210825092116.149975-3-wangkefeng.wang@huawei.com \
    --to=wangkefeng.wang@huawei.com \
    --cc=akpm@linux-foundation.org \
    --cc=dvyukov@google.com \
    --cc=elver@google.com \
    --cc=glider@google.com \
    --cc=kasan-dev@googlegroups.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@armlinux.org.uk \
    --subject='Re: [PATCH 2/4] ARM: mm: Provide is_write_fault()' \
    /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

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).