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Groups > linux.kernel > #1249780
| From | Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH 3.10 51/54] x86: Add 1/2/4/8 byte optimization to 64bit __copy_{from,to}_user_inatomic |
| Date | 2015-10-18 05:30 +0200 |
| Message-ID | <qkMPy-19j-67@gated-at.bofh.it> (permalink) |
| References | <qkMmu-i6-3@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
3.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Andi Kleen <ak@linux.intel.com>
commit ff47ab4ff3cddfa7bc1b25b990e24abe2ae474ff upstream.
The 64bit __copy_{from,to}_user_inatomic always called
copy_from_user_generic, but skipped the special optimizations for 1/2/4/8
byte accesses.
This especially hurts the futex call, which accesses the 4 byte futex
user value with a complicated fast string operation in a function call,
instead of a single movl.
Use __copy_{from,to}_user for _inatomic instead to get the same
optimizations. The only problem was the might_fault() in those functions.
So move that to new wrapper and call __copy_{f,t}_user_nocheck()
from *_inatomic directly.
32bit already did this correctly by duplicating the code.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1376687844-19857-2-git-send-email-andi@firstfloor.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/x86/include/asm/uaccess_64.h | 24 ++++++++++++++++++------
1 file changed, 18 insertions(+), 6 deletions(-)
--- a/arch/x86/include/asm/uaccess_64.h
+++ b/arch/x86/include/asm/uaccess_64.h
@@ -77,11 +77,10 @@ int copy_to_user(void __user *dst, const
}
static __always_inline __must_check
-int __copy_from_user(void *dst, const void __user *src, unsigned size)
+int __copy_from_user_nocheck(void *dst, const void __user *src, unsigned size)
{
int ret = 0;
- might_fault();
if (!__builtin_constant_p(size))
return copy_user_generic(dst, (__force void *)src, size);
switch (size) {
@@ -121,11 +120,17 @@ int __copy_from_user(void *dst, const vo
}
static __always_inline __must_check
-int __copy_to_user(void __user *dst, const void *src, unsigned size)
+int __copy_from_user(void *dst, const void __user *src, unsigned size)
+{
+ might_fault();
+ return __copy_from_user_nocheck(dst, src, size);
+}
+
+static __always_inline __must_check
+int __copy_to_user_nocheck(void __user *dst, const void *src, unsigned size)
{
int ret = 0;
- might_fault();
if (!__builtin_constant_p(size))
return copy_user_generic((__force void *)dst, src, size);
switch (size) {
@@ -165,6 +170,13 @@ int __copy_to_user(void __user *dst, con
}
static __always_inline __must_check
+int __copy_to_user(void __user *dst, const void *src, unsigned size)
+{
+ might_fault();
+ return __copy_to_user_nocheck(dst, src, size);
+}
+
+static __always_inline __must_check
int __copy_in_user(void __user *dst, const void __user *src, unsigned size)
{
int ret = 0;
@@ -220,13 +232,13 @@ int __copy_in_user(void __user *dst, con
static __must_check __always_inline int
__copy_from_user_inatomic(void *dst, const void __user *src, unsigned size)
{
- return copy_user_generic(dst, (__force const void *)src, size);
+ return __copy_from_user_nocheck(dst, (__force const void *)src, size);
}
static __must_check __always_inline int
__copy_to_user_inatomic(void __user *dst, const void *src, unsigned size)
{
- return copy_user_generic((__force void *)dst, src, size);
+ return __copy_to_user_nocheck((__force void *)dst, src, size);
}
extern long __copy_user_nocache(void *dst, const void __user *src,
--
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[PATCH 3.10 00/54] 3.10.91-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 43/54] IB/qib: Change lkey table allocation to support more MRs Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 18/54] dm btree: add ref counting ops for the leaves of top level btrees Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 27/54] usb: xhci: Add support for URB_ZERO_PACKET to bulk/sg transfers Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 20/54] dm raid: fix round up of default region size Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 40/54] powerpc/MSI: Fix race condition in tearing down MSI interrupts Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 33/54] regmap: debugfs: Dont bother actually printing when calculating max length Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 30/54] ipvs: fix crash with sync protocol v0 and FTP Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 38/54] MIPS: dma-default: Fix 32-bit fall back to GFP_DMA Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 48/54] bonding: correct the MAC address for "follow" fail_over_mac policy Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 36/54] usb: Add device quirk for Logitech PTZ cameras Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 31/54] udf: Check length of extended attributes and allocation descriptors Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 19/54] USB: option: add ZTE PIDs Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 05/54] x86/apic: Serialize LVTT and TSC_DEADLINE writes Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:00 +0200
[PATCH 3.10 06/54] x86/platform: Fix Geode LX timekeeping in the generic x86 build Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:10 +0200
[PATCH 3.10 09/54] x86/xen: Support kexec/kdump in HVM guests by doing a soft reset Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:10 +0200
[PATCH 3.10 07/54] Use WARN_ON_ONCE for missing X86_FEATURE_NRIPS Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:10 +0200
[PATCH 3.10 08/54] x86/mm: Set NX on gap between __ex_table and rodata Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:10 +0200
[PATCH 3.10 24/54] USB: whiteheat: fix potential null-deref at probe Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 21/54] netfilter: nf_conntrack: Support expectations in different zones Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 26/54] xhci: change xhci 1.0 only restrictions to support xhci 1.1 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 25/54] usb: xhci: Clear XHCI_STATE_DYING on start Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 50/54] genirq: Fix race in register_irq_proc() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 17/54] staging: comedi: adl_pci7x3x: fix digital output on PCI-7230 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 22/54] disabling oplocks/leases via module parm enable_oplocks broken for SMB3 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 23/54] drm: Reject DRI1 hw lock ioctl functions for kms drivers Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 52/54] dm cache: fix NULL pointer when switching from cleaner policy Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 53/54] staging: speakup: fix speakup-r regression Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 51/54] x86: Add 1/2/4/8 byte optimization to 64bit __copy_{from,to}_user_inatomic Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:30 +0200
[PATCH 3.10 02/54] perf header: Fixup reading of HEADER_NRCPUS feature Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 01/54] scsi: fix scsi_error_handler vs. scsi_host_dev_release race Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 03/54] ARM: 8429/1: disable GCC SRA optimization Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 16/54] btrfs: skip waiting on ordered range for special files Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 10/54] spi: Fix documentation of spi_alloc_master() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 14/54] ASoC: fix broken pxa SoC support Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 13/54] ALSA: synth: Fix conflicting OSS device registration on AWE32 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 15/54] ASoC: dwc: correct irq clear method Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 04/54] windfarm: decrement client count when unregistering Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:40 +0200
[PATCH 3.10 11/54] spi: spi-pxa2xx: Check status register to determine if SSSR_TINT is disabled Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 05:50 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Willy Tarreau <w@1wt.eu> - 2015-10-18 09:10 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 18:10 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Willy Tarreau <w@1wt.eu> - 2015-10-18 21:20 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-18 21:40 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Guenter Roeck <linux@roeck-us.net> - 2015-10-19 06:10 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-19 17:20 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Shuah Khan <shuahkh@osg.samsung.com> - 2015-10-19 17:20 +0200
Re: [PATCH 3.10 00/54] 3.10.91-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-10-22 23:40 +0200
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