Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752228AbaLELSb (ORCPT ); Fri, 5 Dec 2014 06:18:31 -0500 Received: from e06smtp17.uk.ibm.com ([195.75.94.113]:37153 "EHLO e06smtp17.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751694AbaLELS1 (ORCPT ); Fri, 5 Dec 2014 06:18:27 -0500 From: David Hildenbrand To: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Cc: benh@kernel.crashing.org, paulus@samba.org, akpm@linux-foundation.org, heiko.carstens@de.ibm.com, dahi@linux.vnet.ibm.com, schwidefsky@de.ibm.com, borntraeger@de.ibm.com, mst@redhat.com, tglx@linutronix.de, David.Laight@ACULAB.COM, peterz@infradead.org, hughd@google.com, hocko@suse.cz Subject: [PATCH v1 4/5] uaccess: clearify that uaccess may only sleep if pagefaults are not disabled Date: Fri, 5 Dec 2014 12:18:08 +0100 Message-Id: <1417778289-51567-5-git-send-email-dahi@linux.vnet.ibm.com> X-Mailer: git-send-email 1.8.5.5 In-Reply-To: <1417778289-51567-1-git-send-email-dahi@linux.vnet.ibm.com> References: <1417778289-51567-1-git-send-email-dahi@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14120511-0029-0000-0000-0000020973A9 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In general, non-atomic variants of user access functions may not sleep if pagefaults are disabled. Let's update all relevant comments in uaccess code. This also refelects the might_sleep() checks in might_fault(). Signed-off-by: David Hildenbrand --- arch/avr32/include/asm/uaccess.h | 12 ++++++---- arch/hexagon/include/asm/uaccess.h | 3 ++- arch/m32r/include/asm/uaccess.h | 30 +++++++++++++++-------- arch/microblaze/include/asm/uaccess.h | 6 +++-- arch/mips/include/asm/uaccess.h | 45 +++++++++++++++++++++++------------ arch/s390/include/asm/uaccess.h | 15 ++++++++---- arch/score/include/asm/uaccess.h | 15 ++++++++---- arch/tile/include/asm/uaccess.h | 21 ++++++++++------ arch/x86/include/asm/uaccess.h | 15 ++++++++---- arch/x86/include/asm/uaccess_32.h | 6 +++-- arch/x86/lib/usercopy_32.c | 6 +++-- lib/strnlen_user.c | 6 +++-- 12 files changed, 120 insertions(+), 60 deletions(-) diff --git a/arch/avr32/include/asm/uaccess.h b/arch/avr32/include/asm/uaccess.h index 245b2ee..6b6dd58 100644 --- a/arch/avr32/include/asm/uaccess.h +++ b/arch/avr32/include/asm/uaccess.h @@ -97,7 +97,8 @@ static inline __kernel_size_t __copy_from_user(void *to, * @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 not + * disabled. * * This macro copies a single simple value from kernel space to user * space. It supports simple types like char and int, but not larger @@ -116,7 +117,8 @@ static inline __kernel_size_t __copy_from_user(void *to, * @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 not + * disabled. * * This macro copies a single simple variable from user space to kernel * space. It supports simple types like char and int, but not larger @@ -136,7 +138,8 @@ static inline __kernel_size_t __copy_from_user(void *to, * @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 not + * disabled. * * This macro copies a single simple value from kernel space to user * space. It supports simple types like char and int, but not larger @@ -158,7 +161,8 @@ static inline __kernel_size_t __copy_from_user(void *to, * @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 not + * disabled. * * This macro copies a single simple variable from user space to kernel * space. It supports simple types like char and int, but not larger diff --git a/arch/hexagon/include/asm/uaccess.h b/arch/hexagon/include/asm/uaccess.h index e4127e4..af98618 100644 --- a/arch/hexagon/include/asm/uaccess.h +++ b/arch/hexagon/include/asm/uaccess.h @@ -36,7 +36,8 @@ * @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 not + * disabled. * * Checks if a pointer to a block of memory in user space is valid. * diff --git a/arch/m32r/include/asm/uaccess.h b/arch/m32r/include/asm/uaccess.h index 84fe7ba..83bfa33 100644 --- a/arch/m32r/include/asm/uaccess.h +++ b/arch/m32r/include/asm/uaccess.h @@ -91,7 +91,8 @@ static inline void set_fs(mm_segment_t s) * @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 not + * disabled. * * Checks if a pointer to a block of memory in user space is valid. * @@ -155,7 +156,8 @@ extern int fixup_exception(struct pt_regs *regs); * @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 not + * disabled. * * This macro copies a single simple variable from user space to kernel * space. It supports simple types like char and int, but not larger @@ -175,7 +177,8 @@ extern int fixup_exception(struct pt_regs *regs); * @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 not + * disabled. * * This macro copies a single simple value from kernel space to user * space. It supports simple types like char and int, but not larger @@ -194,7 +197,8 @@ extern int fixup_exception(struct pt_regs *regs); * @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 not + * disabled. * * This macro copies a single simple variable from user space to kernel * space. It supports simple types like char and int, but not larger @@ -274,7 +278,8 @@ do { \ * @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 not + * disabled. * * This macro copies a single simple value from kernel space to user * space. It supports simple types like char and int, but not larger @@ -568,7 +573,8 @@ unsigned long __generic_copy_from_user(void *, const void __user *, unsigned lon * @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 not + * disabled. * * Copy data from kernel space to user space. Caller must check * the specified block with access_ok() before calling this function. @@ -588,7 +594,8 @@ unsigned long __generic_copy_from_user(void *, const void __user *, unsigned lon * @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 not + * disabled. * * Copy data from kernel space to user space. * @@ -606,7 +613,8 @@ unsigned long __generic_copy_from_user(void *, const void __user *, unsigned lon * @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 not + * disabled. * * Copy data from user space to kernel space. Caller must check * the specified block with access_ok() before calling this function. @@ -626,7 +634,8 @@ unsigned long __generic_copy_from_user(void *, const void __user *, unsigned lon * @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 not + * disabled. * * Copy data from user space to kernel space. * @@ -677,7 +686,8 @@ unsigned long clear_user(void __user *mem, unsigned 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 not + * disabled. * * Get the size of a NUL-terminated string in user space. * diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h index 59a89a6..53bfbb8 100644 --- a/arch/microblaze/include/asm/uaccess.h +++ b/arch/microblaze/include/asm/uaccess.h @@ -178,7 +178,8 @@ extern long __user_bad(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 not + * disabled. * * This macro copies a single simple variable from user space to kernel * space. It supports simple types like char and int, but not larger @@ -290,7 +291,8 @@ extern long __user_bad(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 not + * disabled. * * This macro copies a single simple value from kernel space to user * space. It supports simple types like char and int, but not larger diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h index 22a5624..eded117 100644 --- a/arch/mips/include/asm/uaccess.h +++ b/arch/mips/include/asm/uaccess.h @@ -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 not + * disabled. * * 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 not + * disabled. * * 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 not + * disabled. * * 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 not + * disabled. * * 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 not + * disabled. * * 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 not + * disabled. * * 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 not + * disabled. * * 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 not + * disabled. * * 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 not + * disabled. * * 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 not + * disabled. * * 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 not + * disabled. * * 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 not + * disabled. * * 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 not + * disabled. * * Copy data from user space to kernel space. * @@ -1356,7 +1369,8 @@ static inline long __strlen_user(const char __user *s) * 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 not + * disabled. * * Get the size of a NUL-terminated string in user space. * @@ -1425,7 +1439,8 @@ 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 not + * disabled. * * Get the size of a NUL-terminated string in user space. * diff --git a/arch/s390/include/asm/uaccess.h b/arch/s390/include/asm/uaccess.h index cd4c68e..1291da5 100644 --- a/arch/s390/include/asm/uaccess.h +++ b/arch/s390/include/asm/uaccess.h @@ -98,7 +98,8 @@ static inline unsigned long extable_fixup(const struct exception_table_entry *x) * @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 not + * disabled. * * Copy data from user space to kernel space. Caller must check * the specified block with access_ok() before calling this function. @@ -118,7 +119,8 @@ unsigned long __must_check __copy_from_user(void *to, const void __user *from, * @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 not + * disabled. * * Copy data from kernel space to user space. Caller must check * the specified block with access_ok() before calling this function. @@ -264,7 +266,8 @@ int __get_user_bad(void) __attribute__((noreturn)); * @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 not + * disabled. * * Copy data from kernel space to user space. * @@ -290,7 +293,8 @@ __compiletime_warning("copy_from_user() buffer size is not provably correct") * @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 not + * disabled. * * Copy data from user space to kernel space. * @@ -348,7 +352,8 @@ static inline unsigned long strnlen_user(const char __user *src, unsigned long n * 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 not + * disabled. * * Get the size of a NUL-terminated string in user space. * diff --git a/arch/score/include/asm/uaccess.h b/arch/score/include/asm/uaccess.h index ab66ddd..010a800 100644 --- a/arch/score/include/asm/uaccess.h +++ b/arch/score/include/asm/uaccess.h @@ -36,7 +36,8 @@ * @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 not + * disabled. * * Checks if a pointer to a block of memory in user space is valid. * @@ -61,7 +62,8 @@ * @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 not + * disabled. * * This macro copies a single simple value from kernel space to user * space. It supports simple types like char and int, but not larger @@ -79,7 +81,8 @@ * @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 not + * disabled. * * This macro copies a single simple variable from user space to kernel * space. It supports simple types like char and int, but not larger @@ -98,7 +101,8 @@ * @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 not + * disabled. * * This macro copies a single simple value from kernel space to user * space. It supports simple types like char and int, but not larger @@ -119,7 +123,8 @@ * @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 not + * disabled. * * This macro copies a single simple variable from user space to kernel * space. It supports simple types like char and int, but not larger diff --git a/arch/tile/include/asm/uaccess.h b/arch/tile/include/asm/uaccess.h index b6cde32..9efe668 100644 --- a/arch/tile/include/asm/uaccess.h +++ b/arch/tile/include/asm/uaccess.h @@ -78,7 +78,8 @@ int __range_ok(unsigned long addr, unsigned long size); * @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 not + * disabled. * * Checks if a pointer to a block of memory in user space is valid. * @@ -192,7 +193,8 @@ extern int __get_user_bad(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 not + * disabled. * * This macro copies a single simple variable from user space to kernel * space. It supports simple types like char and int, but not larger @@ -272,7 +274,8 @@ extern int __put_user_bad(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 not + * disabled. * * This macro copies a single simple value from kernel space to user * space. It supports simple types like char and int, but not larger @@ -327,7 +330,8 @@ extern int __put_user_bad(void) * @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 not + * disabled. * * Copy data from kernel space to user space. Caller must check * the specified block with access_ok() before calling this function. @@ -363,7 +367,8 @@ copy_to_user(void __user *to, const void *from, unsigned long 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 not + * disabled. * * Copy data from user space to kernel space. Caller must check * the specified block with access_ok() before calling this function. @@ -434,7 +439,8 @@ static inline unsigned long __must_check copy_from_user(void *to, * @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 not + * disabled. * * Copy data from user space to user space. Caller must check * the specified blocks with access_ok() before calling this function. @@ -466,7 +472,8 @@ copy_in_user(void __user *to, const void __user *from, unsigned long n) * 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 not + * disabled. * * Get the size of a NUL-terminated string in user space. * diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index 0d592e0..014d8cb 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -74,7 +74,8 @@ static inline bool __chk_range_not_ok(unsigned long addr, unsigned long size, un * @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 not + * disabled. * * Checks if a pointer to a block of memory in user space is valid. * @@ -145,7 +146,8 @@ __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL)) * @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 not + * disabled. * * This macro copies a single simple variable from user space to kernel * space. It supports simple types like char and int, but not larger @@ -240,7 +242,8 @@ extern void __put_user_8(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 not + * disabled. * * This macro copies a single simple value from kernel space to user * space. It supports simple types like char and int, but not larger @@ -455,7 +458,8 @@ struct __large_struct { unsigned long buf[100]; }; * @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 not + * disabled. * * This macro copies a single simple variable from user space to kernel * space. It supports simple types like char and int, but not larger @@ -479,7 +483,8 @@ struct __large_struct { unsigned long buf[100]; }; * @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 not + * disabled. * * This macro copies a single simple value from kernel space to user * space. It supports simple types like char and int, but not larger diff --git a/arch/x86/include/asm/uaccess_32.h b/arch/x86/include/asm/uaccess_32.h index 3c03a5d..ae5b37f 100644 --- a/arch/x86/include/asm/uaccess_32.h +++ b/arch/x86/include/asm/uaccess_32.h @@ -70,7 +70,8 @@ __copy_to_user_inatomic(void __user *to, const void *from, unsigned long 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 not + * disabled. * * Copy data from kernel space to user space. Caller must check * the specified block with access_ok() before calling this function. @@ -117,7 +118,8 @@ __copy_from_user_inatomic(void *to, const void __user *from, unsigned long 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 not + * disabled. * * Copy data from user space to kernel space. Caller must check * the specified block with access_ok() before calling this function. diff --git a/arch/x86/lib/usercopy_32.c b/arch/x86/lib/usercopy_32.c index e2f5e21..64ba86e 100644 --- a/arch/x86/lib/usercopy_32.c +++ b/arch/x86/lib/usercopy_32.c @@ -647,7 +647,8 @@ EXPORT_SYMBOL(__copy_from_user_ll_nocache_nozero); * @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 not + * disabled. * * Copy data from kernel space to user space. * @@ -668,7 +669,8 @@ EXPORT_SYMBOL(_copy_to_user); * @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 not + * disabled. * * Copy data from user space to kernel space. * diff --git a/lib/strnlen_user.c b/lib/strnlen_user.c index a28df52..0013abd 100644 --- a/lib/strnlen_user.c +++ b/lib/strnlen_user.c @@ -84,7 +84,8 @@ static inline long do_strnlen_user(const char __user *src, unsigned long count, * @str: The string to measure. * @count: Maximum count (including NUL character) * - * Context: User context only. This function may sleep. + * Context: User context only. This function may sleep if pagefaults are not + * disabled. * * Get the size of a NUL-terminated string in user space. * @@ -113,7 +114,8 @@ EXPORT_SYMBOL(strnlen_user); * strlen_user: - Get the size of a user string INCLUDING final NUL. * @str: The string to measure. * - * Context: User context only. This function may sleep. + * Context: User context only. This function may sleep if pagefaults are not + * disabled. * * Get the size of a NUL-terminated string in user space. * -- 1.8.5.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/