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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(). called pkey_set().
int real_prot = PROT_READ|PROT_WRITE; 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); ptr = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
ret = pkey_mprotect(ptr, PAGE_SIZE, real_prot, pkey); ret = pkey_mprotect(ptr, PAGE_SIZE, real_prot, pkey);
... application runs here ... application runs here
@ -42,9 +42,9 @@ called pkey_set().
Now, if the application needs to update the data at 'ptr', it can Now, if the application needs to update the data at 'ptr', it can
gain access, do the update, then remove its write access: 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 *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 Now when it frees the memory, it will also free the pkey since it
is no longer in use: is no longer in use: