Patch "arm64: Ignore the 'write' ESR flag on cache maintenance faults" has been added to the 3.9-stable tree

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



This is a note to let you know that I've just added the patch titled

    arm64: Ignore the 'write' ESR flag on cache maintenance faults

to the 3.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     arm64-ignore-the-write-esr-flag-on-cache-maintenance-faults.patch
and it can be found in the queue-3.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.


>From 0e7f7bcc3fc87489cda5aa6aff8ce40eed912279 Mon Sep 17 00:00:00 2001
From: Catalin Marinas <catalin.marinas@xxxxxxx>
Date: Tue, 7 May 2013 16:57:06 +0100
Subject: arm64: Ignore the 'write' ESR flag on cache maintenance faults

From: Catalin Marinas <catalin.marinas@xxxxxxx>

commit 0e7f7bcc3fc87489cda5aa6aff8ce40eed912279 upstream.

ESR.WnR bit is always set on data cache maintenance faults even though
the page is not required to have write permission. If a translation
fault (page not yet mapped) happens for read-only user address range,
Linux incorrectly assumes a permission fault. This patch adds the check
of the ESR.CM bit during the page fault handling to ignore the 'write'
flag.

Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Reported-by: Tim Northover <Tim.Northover@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 arch/arm64/mm/fault.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -148,6 +148,7 @@ void do_bad_area(unsigned long addr, uns
 #define VM_FAULT_BADACCESS	0x020000
 
 #define ESR_WRITE		(1 << 6)
+#define ESR_CM			(1 << 8)
 #define ESR_LNX_EXEC		(1 << 24)
 
 /*
@@ -206,7 +207,7 @@ static int __kprobes do_page_fault(unsig
 	struct task_struct *tsk;
 	struct mm_struct *mm;
 	int fault, sig, code;
-	int write = esr & ESR_WRITE;
+	bool write = (esr & ESR_WRITE) && !(esr & ESR_CM);
 	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE |
 		(write ? FAULT_FLAG_WRITE : 0);
 


Patches currently in stable-queue which might be from catalin.marinas@xxxxxxx are

queue-3.9/arm64-ignore-the-write-esr-flag-on-cache-maintenance-faults.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]