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x86/mm/pkeys: Fix typo in Documentation/x86/protection-keys.txt 

Replace PKEY_DENY_WRITE with PKEY_DISABLE_WRITE,
to match the source code.

Signed-off-by: Wang Kai <morgan.wang@huawei.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: corbet@lwn.net
Cc: dave.hansen@intel.com
Cc: dave.hansen@linux.intel.com
Cc: linux-doc@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
zero-colors
Wang Kai 2017-07-24 21:03:46 +08:00 committed by Ingo Molnar
parent 04b67022fb
commit f90e2d9a52
1 changed files with 3 additions and 3 deletions
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6
Documentation/x86/protection-keys.txt
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@ -34,7 +34,7 @@ with a key. In this example WRPKRU is wrapped by a C function
called pkey_set().
int real_prot = PROT_READ|PROT_WRITE;
pkey = pkey_alloc(0, PKEY_DENY_WRITE);
pkey = pkey_alloc(0, PKEY_DISABLE_WRITE);
ptr = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
ret = pkey_mprotect(ptr, PAGE_SIZE, real_prot, pkey);
... application runs here
@ -42,9 +42,9 @@ called pkey_set().
Now, if the application needs to update the data at 'ptr', it can
gain access, do the update, then remove its write access:
pkey_set(pkey, 0); // clear PKEY_DENY_WRITE
pkey_set(pkey, 0); // clear PKEY_DISABLE_WRITE
*ptr = foo; // assign something
pkey_set(pkey, PKEY_DENY_WRITE); // set PKEY_DENY_WRITE again
pkey_set(pkey, PKEY_DISABLE_WRITE); // set PKEY_DISABLE_WRITE again
Now when it frees the memory, it will also free the pkey since it
is no longer in use: