diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2016-01-12 11:01:12 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2016-01-12 11:01:12 +0100 |
| commit | 1f16f116b01c110db20ab808562c8b8bc3ee3d6e (patch) | |
| tree | 44db563f64cf5f8d62af8f99a61e2b248c44ea3a /arch/arm/lib/uaccess_with_memcpy.c | |
| parent | 03724ac3d48f8f0e3caf1d30fa134f8fd96c94e2 (diff) | |
| parent | f9eccf24615672896dc13251410c3f2f33a14f95 (diff) | |
| download | lwn-1f16f116b01c110db20ab808562c8b8bc3ee3d6e.tar.gz lwn-1f16f116b01c110db20ab808562c8b8bc3ee3d6e.zip | |
Merge branches 'clockevents/4.4-fixes' and 'clockevents/4.5-fixes' of http://git.linaro.org/people/daniel.lezcano/linux into timers/urgent
Pull in fixes from Daniel Lezcano:
- Fix the vt8500 timer leading to a system lock up when dealing with too
small delta (Roman Volkov)
- Select the CLKSRC_MMIO when the fsl_ftm_timer is enabled with COMPILE_TEST
(Daniel Lezcano)
- Prevent to compile timers using the 'iomem' API when the architecture has
not HAS_IOMEM set (Richard Weinberger)
Diffstat (limited to 'arch/arm/lib/uaccess_with_memcpy.c')
| -rw-r--r-- | arch/arm/lib/uaccess_with_memcpy.c | 29 |
1 files changed, 23 insertions, 6 deletions
diff --git a/arch/arm/lib/uaccess_with_memcpy.c b/arch/arm/lib/uaccess_with_memcpy.c index d72b90905132..588bbc288396 100644 --- a/arch/arm/lib/uaccess_with_memcpy.c +++ b/arch/arm/lib/uaccess_with_memcpy.c @@ -88,6 +88,7 @@ pin_page_for_write(const void __user *_addr, pte_t **ptep, spinlock_t **ptlp) static unsigned long noinline __copy_to_user_memcpy(void __user *to, const void *from, unsigned long n) { + unsigned long ua_flags; int atomic; if (unlikely(segment_eq(get_fs(), KERNEL_DS))) { @@ -118,7 +119,9 @@ __copy_to_user_memcpy(void __user *to, const void *from, unsigned long n) if (tocopy > n) tocopy = n; + ua_flags = uaccess_save_and_enable(); memcpy((void *)to, from, tocopy); + uaccess_restore(ua_flags); to += tocopy; from += tocopy; n -= tocopy; @@ -145,14 +148,21 @@ arm_copy_to_user(void __user *to, const void *from, unsigned long n) * With frame pointer disabled, tail call optimization kicks in * as well making this test almost invisible. */ - if (n < 64) - return __copy_to_user_std(to, from, n); - return __copy_to_user_memcpy(to, from, n); + if (n < 64) { + unsigned long ua_flags = uaccess_save_and_enable(); + n = __copy_to_user_std(to, from, n); + uaccess_restore(ua_flags); + } else { + n = __copy_to_user_memcpy(to, from, n); + } + return n; } static unsigned long noinline __clear_user_memset(void __user *addr, unsigned long n) { + unsigned long ua_flags; + if (unlikely(segment_eq(get_fs(), KERNEL_DS))) { memset((void *)addr, 0, n); return 0; @@ -175,7 +185,9 @@ __clear_user_memset(void __user *addr, unsigned long n) if (tocopy > n) tocopy = n; + ua_flags = uaccess_save_and_enable(); memset((void *)addr, 0, tocopy); + uaccess_restore(ua_flags); addr += tocopy; n -= tocopy; @@ -193,9 +205,14 @@ out: unsigned long arm_clear_user(void __user *addr, unsigned long n) { /* See rational for this in __copy_to_user() above. */ - if (n < 64) - return __clear_user_std(addr, n); - return __clear_user_memset(addr, n); + if (n < 64) { + unsigned long ua_flags = uaccess_save_and_enable(); + n = __clear_user_std(addr, n); + uaccess_restore(ua_flags); + } else { + n = __clear_user_memset(addr, n); + } + return n; } #if 0 |