xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

mm/uaccess, mm/fault: Clarify that uaccess may only sleep if pagefaults are enabled

Browse Source 
In general, non-atomic variants of user access functions must not sleep
if pagefaults are disabled.

Let's update all relevant comments in uaccess code. This also reflects
the might_sleep() checks in might_fault().

Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-4-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
David Hildenbrand
2015-05-11 17:52:08 +02:00
committed by Ingo Molnar
parent 9ec23531fd
commit b3c395ef55
12 changed files with 118 additions and 59 deletions
Download Patch File Download Diff File Expand all files Collapse all files

45
arch/mips/include/asm/uaccess.h
View File

@@ -103,7 +103,8 @@ extern u64 __ua_limit;
* @addr: User space pointer to start of block to check
* @size: Size of block to check
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Checks if a pointer to a block of memory in user space is valid.
*
@@ -138,7 +139,8 @@ extern u64 __ua_limit;
* @x: Value to copy to user space.
* @ptr: Destination address, in user space.
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* This macro copies a single simple value from kernel space to user
* space. It supports simple types like char and int, but not larger
@@ -157,7 +159,8 @@ extern u64 __ua_limit;
* @x: Variable to store result.
* @ptr: Source address, in user space.
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* This macro copies a single simple variable from user space to kernel
* space. It supports simple types like char and int, but not larger
@@ -177,7 +180,8 @@ extern u64 __ua_limit;
* @x: Value to copy to user space.
* @ptr: Destination address, in user space.
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* This macro copies a single simple value from kernel space to user
* space. It supports simple types like char and int, but not larger
@@ -199,7 +203,8 @@ extern u64 __ua_limit;
* @x: Variable to store result.
* @ptr: Source address, in user space.
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* This macro copies a single simple variable from user space to kernel
* space. It supports simple types like char and int, but not larger
@@ -498,7 +503,8 @@ extern void __put_user_unknown(void);
* @x: Value to copy to user space.
* @ptr: Destination address, in user space.
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* This macro copies a single simple value from kernel space to user
* space. It supports simple types like char and int, but not larger
@@ -517,7 +523,8 @@ extern void __put_user_unknown(void);
* @x: Variable to store result.
* @ptr: Source address, in user space.
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* This macro copies a single simple variable from user space to kernel
* space. It supports simple types like char and int, but not larger
@@ -537,7 +544,8 @@ extern void __put_user_unknown(void);
* @x: Value to copy to user space.
* @ptr: Destination address, in user space.
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* This macro copies a single simple value from kernel space to user
* space. It supports simple types like char and int, but not larger
@@ -559,7 +567,8 @@ extern void __put_user_unknown(void);
* @x: Variable to store result.
* @ptr: Source address, in user space.
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* This macro copies a single simple variable from user space to kernel
* space. It supports simple types like char and int, but not larger
@@ -815,7 +824,8 @@ extern size_t __copy_user(void *__to, const void *__from, size_t __n);
* @from: Source address, in kernel space.
* @n: Number of bytes to copy.
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Copy data from kernel space to user space. Caller must check
* the specified block with access_ok() before calling this function.
@@ -888,7 +898,8 @@ extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
* @from: Source address, in kernel space.
* @n: Number of bytes to copy.
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Copy data from kernel space to user space.
*
@@ -1075,7 +1086,8 @@ extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n);
* @from: Source address, in user space.
* @n: Number of bytes to copy.
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Copy data from user space to kernel space. Caller must check
* the specified block with access_ok() before calling this function.
@@ -1107,7 +1119,8 @@ extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n);
* @from: Source address, in user space.
* @n: Number of bytes to copy.
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Copy data from user space to kernel space.
*
@@ -1329,7 +1342,8 @@ strncpy_from_user(char *__to, const char __user *__from, long __len)
* strlen_user: - Get the size of a string in user space.
* @str: The string to measure.
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Get the size of a NUL-terminated string in user space.
*
@@ -1398,7 +1412,8 @@ static inline long __strnlen_user(const char __user *s, long n)
* strnlen_user: - Get the size of a string in user space.
* @str: The string to measure.
*
* Context: User context only. This function may sleep.
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Get the size of a NUL-terminated string in user space.
*