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2010-09-19ARM: 6380/1: Introduce __sync_icache_dcache() for VIPT cachesCatalin Marinas4-6/+64
On SMP systems, there is a small chance of a PTE becoming visible to a different CPU before the current cache maintenance operations in update_mmu_cache(). To avoid this, cache maintenance must be handled in set_pte_at() (similar to IA-64 and PowerPC). This patch provides a unified VIPT cache handling mechanism and implements the __sync_icache_dcache() function for ARMv6 onwards architectures. It is called from set_pte_at() and replaces the update_mmu_cache(). The latter is still used on VIVT hardware where a vm_area_struct is required. Tested-by: Rabin Vincent <rabin.vincent@stericsson.com> Cc: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-09-19ARM: 6379/1: Assume new page cache pages have dirty D-cacheCatalin Marinas8-10/+17
There are places in Linux where writes to newly allocated page cache pages happen without a subsequent call to flush_dcache_page() (several PIO drivers including USB HCD). This patch changes the meaning of PG_arch_1 to be PG_dcache_clean and always flush the D-cache for a newly mapped page in update_mmu_cache(). The patch also sets the PG_arch_1 bit in the DMA cache maintenance function to avoid additional cache flushing in update_mmu_cache(). Tested-by: Rabin Vincent <rabin.vincent@stericsson.com> Cc: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-09-19ARM: 6378/1: Allow lazy cache flushing via PG_arch_1 for highmem pagesCatalin Marinas1-1/+1
Commit d73cd42 forced non-lazy cache flushing of highmem pages in flush_dcache_page(). This isn't needed since __flush_dcache_page() (called lazily from update_mmu_cache) can handle highmem pages (fixed by commit 7e5a69e). Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-09-17arm: fix really nasty sigreturn bugAl Viro1-0/+2
If a signal hits us outside of a syscall and another gets delivered when we are in sigreturn (e.g. because it had been in sa_mask for the first one and got sent to us while we'd been in the first handler), we have a chance of returning from the second handler to location one insn prior to where we ought to return. If r0 happens to contain -513 (-ERESTARTNOINTR), sigreturn will get confused into doing restart syscall song and dance. Incredible joy to debug, since it manifests as random, infrequent and very hard to reproduce double execution of instructions in userland code... The fix is simple - mark it "don't bother with restarts" in wrapper, i.e. set r8 to 0 in sys_sigreturn and sys_rt_sigreturn wrappers, suppressing the syscall restart handling on return from these guys. They can't legitimately return a restart-worthy error anyway. Testcase: #include <unistd.h> #include <signal.h> #include <stdlib.h> #include <sys/time.h> #include <errno.h> void f(int n) { __asm__ __volatile__( "ldr r0, [%0]\n" "b 1f\n" "b 2f\n" "1:b .\n" "2:\n" : : "r"(&n)); } void handler1(int sig) { } void handler2(int sig) { raise(1); } void handler3(int sig) { exit(0); } main() { struct sigaction s = {.sa_handler = handler2}; struct itimerval t1 = { .it_value = {1} }; struct itimerval t2 = { .it_value = {2} }; signal(1, handler1); sigemptyset(&s.sa_mask); sigaddset(&s.sa_mask, 1); sigaction(SIGALRM, &s, NULL); signal(SIGVTALRM, handler3); setitimer(ITIMER_REAL, &t1, NULL); setitimer(ITIMER_VIRTUAL, &t2, NULL); f(-513); /* -ERESTARTNOINTR */ write(1, "buggered\n", 9); return 1; } Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-17hwmon: (lm95241) Replace rate sysfs attribute with update_intervalGuenter Roeck1-10/+11
update_interval is the matching attribute defined in the hwmon sysfs ABI. Use it. Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-09-17hwmon: (adm1031) Replace update_rate sysfs attribute with update_intervalGuenter Roeck2-23/+27
The attribute reflects an interval, not a rate. Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com> Acked-by: Ira W. Snyder <iws@ovro.caltech.edu> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-09-17hwmon: (w83627ehf) Use proper exit sequenceJonas Jonsson1-0/+1
According to the datasheet for Winbond W83627DHG the proper way to exit the Extended Function Mode is to write 0xaa to the EFER(0x2e or 0x4e). Signed-off-by: Jonas Jonsson <jonas@ludd.ltu.se> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-09-17hwmon: (emc1403) Remove unnecessary hwmon_device_unregisterYong Wang1-1/+0
It is unnecessary and wrong to call hwmon_device_unregister in error handling before hwmon_device_register is called. Signed-off-by: Yong Wang <yong.y.wang@intel.com> Reviewed-by: Guenter Roeck <guenter.roeck@ericsson.com> Cc: stable@kernel.org Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-09-17hwmon: (f75375s) Do not overwrite values read from registersGuillem Jover1-2/+2
All bits in the values read from registers to be used for the next write were getting overwritten, avoid doing so to not mess with the current configuration. Signed-off-by: Guillem Jover <guillem@hadrons.org> Cc: Riku Voipio <riku.voipio@iki.fi> Cc: stable@kernel.org Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-09-17hwmon: (f75375s) Shift control mode to the correct bit positionGuillem Jover1-1/+1
The spec notes that fan0 and fan1 control mode bits are located in bits 7-6 and 5-4 respectively, but the FAN_CTRL_MODE macro was making the bits shift by 5 instead of by 4. Signed-off-by: Guillem Jover <guillem@hadrons.org> Cc: Riku Voipio <riku.voipio@iki.fi> Cc: stable@kernel.org Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-09-17hwmon: New subsystem maintainersJean Delvare1-1/+4
Guenter Roeck volunteered to adopt the hwmon subsystem as long as he wasn't the only maintainer. As this was also my own condition, we can add the two of us as co-maintainers of the hwmon subsystem. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>
2010-09-17hwmon: (lis3lv02d) Prevent NULL pointer dereferenceKuninori Morimoto2-4/+4
If CONFIG_PM was selected and lis3lv02d_platform_data was NULL, the kernel will be panic when halt command run. Reported-by: Yusuke Goda <yusuke.goda.sx@renesas.com> Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Acked-by: Samu Onkalo <samu.p.onkalo@nokia.com> Sigend-off-by: Jean Delvare <khali@linux-fr.org>
2010-09-17GFS2: gfs2_logd should be using interruptible waitsSteven Whitehouse1-1/+1
Looks like this crept in, in a recent update. Reported-by: Krzysztof Urbaniak <urban@bash.org.pl> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2010-09-17md: fix v1.x metadata update when a disk is missing.NeilBrown1-1/+3
If an array with 1.x metadata is assembled with the last disk missing, md doesn't properly record the fact that the disk was missing. This is unlikely to cause a real problem as the event count will be different to the count on the missing disk so it won't be included in the array. However it could still cause confusion. So make sure we clear all the relevant slots, not just the early ones. Signed-off-by: NeilBrown <neilb@suse.de>
2010-09-17md: call md_update_sb even for 'external' metadata arrays.NeilBrown1-1/+1
Now that we depend on md_update_sb to clear variable bits in mddev->flags (rather than trying not to set them) it is important to always call md_update_sb when appropriate. md_check_recovery has this job but explicitly avoids it for ->external metadata arrays. This is not longer appropraite, or needed. However we do want to avoid taking the mddev lock if only MD_CHANGE_PENDING is set as that is not cleared by md_update_sb for external-metadata arrays. Reported-by: "Kwolek, Adam" <adam.kwolek@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
2010-09-17firewire: nosy: fix build when CONFIG_FIREWIRE=NStefan Richter1-1/+1
drivers/firewire/nosy* is a stand-alone driver that does not depend on CONFIG_FIREWIRE. Hence let make descend into drivers/firewire/ also if that option is off. The stand-alone driver drivers/ieee1394/init_ohci1394_dma* will soon be moved into drivers/firewire/ too and will require the same makefile fix. Side effect: As mentioned in https://bugzilla.novell.com/show_bug.cgi?id=586172#c24 this influences the order in which either firewire-ohci or ohci1394 is going to be bound to an OHCI-1394 controller in case of a modular build of both drivers if no modprobe blacklist entries are configured. However, a user of such a setup cannot expect deterministic behavior anyway. The Kconfig help and the migration guide at ieee1394.wiki.kernel.org recommend blacklist entries when a dual IEEE 1394 stack build is being used. (The coexistence period of the two stacks is planned to end soon.) Cc: Michal Marek <mmarek@suse.cz> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-09-16ALSA: pcm - Fix race with proc filesTakashi Iwai1-9/+24
The PCM proc files may open a race against substream close, which can end up with an Oops. Use the open_mutex to protect for it. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-09-16ALSA: pcm - Fix unbalanced pm_qos_requestTakashi Iwai1-0/+2
The pm_qos_request isn't freed properly when OSS PCM emulation is used because it skips snd_pcm_hw_free() call but directly releases the stream. This resulted in Oops later. Tested-by: Simon Kirby <sim@hostway.ca> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-09-16ALSA: HDA: Enable internal speaker on Dell M101zDavid Henningsson1-0/+10
BugLink: http://launchpad.net/bugs/640254 In some cases a magic processing coefficient is needed to enable the internal speaker on Dell M101z. According to Realtek, this processing coefficient is only present on ALC269vb. Cc: stable@kernel.org Signed-off-by: David Henningsson <david.henningsson@canonical.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-09-16drivers/video/via/ioctl.c: prevent reading uninitialized stack memoryDan Rosenberg1-0/+2
The VIAFB_GET_INFO device ioctl allows unprivileged users to read 246 bytes of uninitialized stack memory, because the "reserved" member of the viafb_ioctl_info struct declared on the stack is not altered or zeroed before being copied back to the user. This patch takes care of it. Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com> Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
2010-09-16[IA64] Optimize ticket spinlocks in fsys_rt_sigprocmaskPetr Tesarik1-31/+11
Tony's fix (f574c843191728d9407b766a027f779dcd27b272) has a small bug, it incorrectly uses "r3" as a scratch register in the first of the two unlock paths ... it is also inefficient. Optimize the fast path again. Signed-off-by: Petr Tesarik <ptesarik@suse.cz> Signed-off-by: Tony Luck <tony.luck@intel.com>
2010-09-15watchdog: Enable NXP LPC32XX support in Kconfig (resend)Kevin Wells1-3/+3
The NXP LPC32XX processor use the same watchdog as the Philips PNX4008 processor. Signed-off-by: Kevin Wells <wellsk40@gmail.com> Tested-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2010-09-15watchdog: ts72xx_wdt: disable watchdog at probeMika Westerberg1-0/+3
Since it may be already enabled by bootloader or some other utility. This patch makes sure that the watchdog is disabled before any userspace daemon opens the device. It is also required by the watchdog API. Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2010-09-15watchdog: sb_wdog: release irq and reboot notifier in error path and ↵Akinobu Mita1-3/+9
module_exit() irq and reboot notifier are acquired in module_init() but never released. They should be released correctly, otherwise reloading the module or error during module_init() will cause a problem. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Andrew Sharp <andy.sharp@lsi.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2010-09-15pcmcia pcnet_cs: try setting io_lines to 16 if card setup failsDominik Brodowski1-56/+83
Some pcnet_cs compatible cards require an exact 16-lines match of the ioport areas specified in CIS, but set the "iolines" value in the CIS incorrectly. We can easily work around this issue -- same as we do in serial_cs -- by first trying setting iolines to the CIS-specified value, and then trying a 16-line match. Reported-and-tested-by: Wolfram Sang <w.sang@pengutronix.de> Hardware-supplied-by: Jochen Frieling <j.frieling@pengutronix.de> CC: netdev@vger.kernel.org Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2010-09-15pcmcia: per-device, not per-socket debug messagesDominik Brodowski1-24/+27
As the iomem / ioport setup differs per device, it is much better to print out the device instead of the socket. Tested-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2010-09-15pcmcia serial_cs.c: fix multifunction card handlingDominik Brodowski1-26/+36
We shouldn't overwrite pre-set values, and we should also set the port address to the beginning, and not the end of the 8-port range. CC: linux-serial@vger.kernel.org Reported-by: Komuro <komurojun-mbn@nifty.com> Hardware-supplied-by: Jochen Frieling <j.frieling@pengutronix.de> Tested-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2010-09-15arch/tile: fix formatting bug in register dumpsChris Metcalf1-1/+1
This cut-and-paste bug was caused by rewriting the register dump code to use only a single printk per line of output. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2010-09-15arch/tile: fix memcpy_fromio()/memcpy_toio() signaturesChris Metcalf1-4/+4
This tripped up a driver (not yet committed to git). Fix it now. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2010-09-15arch/tile: Save and restore extra user state for tilegxChris Metcalf4-7/+34
During context switch, save and restore a couple of additional bits of tilegx user state that can be persistently modified by userspace. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2010-09-15arch/tile: Change struct sigcontext to be more usefulChris Metcalf5-27/+36
Rather than just using pt_regs, it now contains the actual saved state explicitly, similar to pt_regs. By doing it this way, we provide a cleaner API for userspace (or equivalently, we avoid the need for libc to provide its own definition of sigcontext). While we're at it, move PT_FLAGS_xxx to where they are not visible from userspace. And always pass siginfo and mcontext to signal handlers, even if they claim they don't need it, since sometimes they actually try to use it anyway in practice. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2010-09-15arch/tile: finish const-ifying sys_execve()Chris Metcalf3-12/+19
The sys_execve() implementation was properly const-ified but not the declaration, the syscall wrappers, or the compat version. This change completes the constification process. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2010-09-15drm/radeon/kms: only warn on mipmap size checks in r600 cs checker (v2)Alex Deucher1-3/+2
The texture base address registers are in units of 256 bytes. The original CS checker treated these offsets as bytes, so the original check was wrong. I fixed the units in a patch during the 2.6.36 cycle, but this ended up breaking some existing userspace (probably due to a bug in either userspace texture allocation or the drm texture mipmap checker). So for now, until we come up with a better fix, just warn if the mipmap size it too large. This will keep existing userspace working and it should be just as safe as before when we were checking the wrong units. These are GPU MC addresses, so if they fall outside of the VRAM or GART apertures, they end up at the GPU default page, so this should be safe from a security perspective. v2: Just disable the warning. It just spams the log and there's nothing the user can do about it. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Cc: Jerome Glisse <glisse@freedesktop.org> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-09-15MN10300: Fix up the IRQ names for the on-chip serial portsDavid Howells1-11/+11
Fix up the IRQ names for the MN10300 on-chip serial ports in the driver as request_interrupt() no longer allows names containing slashes, giving a warning like the following if one is encountered: ------------[ cut here ]------------ WARNING: at fs/proc/generic.c:323 __xlate_proc_name+0x62/0x7c() name 'ttySM0/Rx' Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-15aio: check for multiplication overflow in do_io_submitJeff Moyer1-0/+3
Tavis Ormandy pointed out that do_io_submit does not do proper bounds checking on the passed-in iocb array:        if (unlikely(nr < 0))                return -EINVAL;        if (unlikely(!access_ok(VERIFY_READ, iocbpp, (nr*sizeof(iocbpp)))))                return -EFAULT;                      ^^^^^^^^^^^^^^^^^^ The attached patch checks for overflow, and if it is detected, the number of iocbs submitted is scaled down to a number that will fit in the long.  This is an ok thing to do, as sys_io_submit is documented as returning the number of iocbs submitted, so callers should handle a return value of less than the 'nr' argument passed in. Reported-by: Tavis Ormandy <taviso@cmpxchg8b.com> Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-15cifs: fix potential double put of TCP session referenceJeff Layton1-3/+3
cifs_get_smb_ses must be called on a server pointer on which it holds an active reference. It first does a search for an existing SMB session. If it finds one, it'll put the server reference and then try to ensure that the negprot is done, etc. If it encounters an error at that point then it'll return an error. There's a potential problem here though. When cifs_get_smb_ses returns an error, the caller will also put the TCP server reference leading to a double-put. Fix this by having cifs_get_smb_ses only put the server reference if it found an existing session that it could use and isn't returning an error. Cc: stable@kernel.org Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-09-15x86-64, compat: Retruncate rax after ia32 syscall entry tracingRoland McGrath1-1/+7
In commit d4d6715, we reopened an old hole for a 64-bit ptracer touching a 32-bit tracee in system call entry. A %rax value set via ptrace at the entry tracing stop gets used whole as a 32-bit syscall number, while we only check the low 32 bits for validity. Fix it by truncating %rax back to 32 bits after syscall_trace_enter, in addition to testing the full 64 bits as has already been added. Reported-by: Ben Hawkes <hawkes@sota.gen.nz> Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-09-15x86-64, compat: Test %rax for the syscall number, not %eaxH. Peter Anvin1-7/+7
On 64 bits, we always, by necessity, jump through the system call table via %rax. For 32-bit system calls, in theory the system call number is stored in %eax, and the code was testing %eax for a valid system call number. At one point we loaded the stored value back from the stack to enforce zero-extension, but that was removed in checkin d4d67150165df8bf1cc05e532f6efca96f907cab. An actual 32-bit process will not be able to introduce a non-zero-extended number, but it can happen via ptrace. Instead of re-introducing the zero-extension, test what we are actually going to use, i.e. %rax. This only adds a handful of REX prefixes to the code. Reported-by: Ben Hawkes <hawkes@sota.gen.nz> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@kernel.org> Cc: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org>
2010-09-15compat: Make compat_alloc_user_space() incorporate the access_ok()H. Peter Anvin10-8/+32
compat_alloc_user_space() expects the caller to independently call access_ok() to verify the returned area. A missing call could introduce problems on some architectures. This patch incorporates the access_ok() check into compat_alloc_user_space() and also adds a sanity check on the length. The existing compat_alloc_user_space() implementations are renamed arch_compat_alloc_user_space() and are used as part of the implementation of the new global function. This patch assumes NULL will cause __get_user()/__put_user() to either fail or access userspace on all architectures. This should be followed by checking the return value of compat_access_user_space() for NULL in the callers, at which time the access_ok() in the callers can also be removed. Reported-by: Ben Hawkes <hawkes@sota.gen.nz> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Chris Metcalf <cmetcalf@tilera.com> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Tony Luck <tony.luck@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: James Bottomley <jejb@parisc-linux.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: <stable@kernel.org>
2010-09-15x86: hpet: Work around hardware stupidityThomas Gleixner3-33/+17
This more or less reverts commits 08be979 (x86: Force HPET readback_cmp for all ATI chipsets) and 30a564be (x86, hpet: Restrict read back to affected ATI chipsets) to the status of commit 8da854c (x86, hpet: Erratum workaround for read after write of HPET comparator). The delta to commit 8da854c is mostly comments and the change from WARN_ONCE to printk_once as we know the call path of this function already. This needs really in depth explanation: First of all the HPET design is a complete failure. Having a counter compare register which generates an interrupt on matching values forces the software to do at least one superfluous readback of the counter register. While it is nice in theory to program "absolute" time events it is practically useless because the timer runs at some absurd frequency which can never be matched to real world units. So we are forced to calculate a relative delta and this forces a readout of the actual counter value, adding the delta and programming the compare register. When the delta is small enough we run into the danger that we program a compare value which is already in the past. Due to the compare for equal nature of HPET we need to read back the counter value after writing the compare rehgister (btw. this is necessary for absolute timeouts as well) to make sure that we did not miss the timer event. We try to work around that by setting the minimum delta to a value which is larger than the theoretical time which elapses between the counter readout and the compare register write, but that's only true in theory. A NMI or SMI which hits between the readout and the write can easily push us beyond that limit. This would result in waiting for the next HPET timer interrupt until the 32bit wraparound of the counter happens which takes about 306 seconds. So we designed the next event function to look like: match = read_cnt() + delta; write_compare_ref(match); return read_cnt() < match ? 0 : -ETIME; At some point we got into trouble with certain ATI chipsets. Even the above "safe" procedure failed. The reason was that the write to the compare register was delayed probably for performance reasons. The theory was that they wanted to avoid the synchronization of the write with the HPET clock, which is understandable. So the write does not hit the compare register directly instead it goes to some intermediate register which is copied to the real compare register in sync with the HPET clock. That opens another window for hitting the dreaded "wait for a wraparound" problem. To work around that "optimization" we added a read back of the compare register which either enforced the update of the just written value or just delayed the readout of the counter enough to avoid the issue. We unfortunately never got any affirmative info from ATI/AMD about this. One thing is sure, that we nuked the performance "optimization" that way completely and I'm pretty sure that the result is worse than before some HW folks came up with those. Just for paranoia reasons I added a check whether the read back compare register value was the same as the value we wrote right before. That paranoia check triggered a couple of years after it was added on an Intel ICH9 chipset. Venki added a workaround (commit 8da854c) which was reading the compare register twice when the first check failed. We considered this to be a penalty in general and restricted the readback (thus the wasted CPU cycles) to the known to be affected ATI chipsets. This turned out to be a utterly wrong decision. 2.6.35 testers experienced massive problems and finally one of them bisected it down to commit 30a564be which spured some further investigation. Finally we got confirmation that the write to the compare register can be delayed by up to two HPET clock cycles which explains the problems nicely. All we can do about this is to go back to Venki's initial workaround in a slightly modified version. Just for the record I need to say, that all of this could have been avoided if hardware designers and of course the HPET committee would have thought about the consequences for a split second. It's out of my comprehension why designing a working timer is so hard. There are two ways to achieve it: 1) Use a counter wrap around aware compare_reg <= counter_reg implementation instead of the easy compare_reg == counter_reg Downsides: - It needs more silicon. - It needs a readout of the counter to apply a relative timeout. This is necessary as the counter does not run in any useful (and adjustable) frequency and there is no guarantee that the counter which is used for timer events is the same which is used for reading the actual time (and therefor for calculating the delta) Upsides: - None 2) Use a simple down counter for relative timer events Downsides: - Absolute timeouts are not possible, which is not a problem at all in the context of an OS and the expected max. latencies/jitter (also see Downsides of #1) Upsides: - It needs less or equal silicon. - It works ALWAYS - It is way faster than a compare register based solution (One write versus one write plus at least one and up to four reads) I would not be so grumpy about all of this, if I would not have been ignored for many years when pointing out these flaws to various hardware folks. I really hate timers (at least those which seem to be designed by janitors). Though finally we got a reasonable explanation plus a solution and I want to thank all the folks involved in chasing it down and providing valuable input to this. Bisected-by: Nix <nix@esperi.org.uk> Reported-by: Artur Skawina <art.08.09@gmail.com> Reported-by: Damien Wyart <damien.wyart@free.fr> Reported-by: John Drescher <drescherjm@gmail.com> Cc: Venkatesh Pallipadi <venki@google.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: stable@kernel.org Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-09-14ALSA: patch_nvhdmi.c: Fix supported sample rate list.Stephen Warren1-1/+1
22050 isn't a valid HDMI sample rate. 32000 is. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-By: Wei Ni <wni@nvidia.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-09-14drm/radeon/kms: force legacy pll algo for RV620 LVDSAlex Deucher1-2/+3
There has been periodic evidence that LVDS, on at least some panels, prefers the dividers selected by the legacy pll algo. This patch forces the use of the legacy pll algo on RV620 LVDS panels. The old behavior (new pll algo) can be selected by setting the new_pll module parameter to 1. Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=30029 Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-09-14drm: fix race between driver loading and userspace open.Dave Airlie2-0/+9
Not 100% sure this is due to BKL removal, its most likely a combination of that + userspace timing changes in udev/plymouth. The drm adds the sysfs device before the driver has completed internal loading, this causes udev to make the node and plymouth to open it before we've completed loading. The proper solution is to delay the sysfs manipulation until later in loading however this causes knock on issues with sysfs connector nodes, so we can use the global mutex to serialise loading and userspace opens. Reported-by: Toni Spets (hifi on #radeon) Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-09-14drm: Use a nondestructive mode for output detect when polling (v2)Chris Wilson12-39/+32
v2: Julien Cristau pointed out that @nondestructive results in double-negatives and confusion when trying to interpret the parameter, so use @force instead. Much easier to type as well. ;-) And fix the miscompilation of vmgfx reported by Sedat Dilek. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-09-14HID: fix hiddev's use of usb_find_interfaceGuillaume Chazarain3-1/+7
My macbook infrared remote control was broken by commit bd25f4dd6972755579d0ea50d1a5ace2e9b00d1a ("HID: hiddev: use usb_find_interface, get rid of BKL"). This device appears in dmesg as: apple 0003:05AC:8242.0001: hiddev0,hidraw0: USB HID v1.11 Device [Apple Computer, Inc. IR Receiver] on usb-0000:00:1d.2-1/input0 It stopped working as lircd was getting ENODEV when opening /dev/usb/hiddev0. AFAICS hiddev_driver is a dummy driver so usb_find_interface(&hiddev_driver) does not find anything. The device is associated with the usbhid driver, so let's do usb_find_interface(&hid_driver) instead. $ ls -l /sys/devices/pci0000:00/0000:00:1d.2/usb7/7-1/7-1:1.0/usb/hiddev0/device/driver lrwxrwxrwx 1 root root 0 2010-09-12 16:28 /sys/devices/pci0000:00/0000:00:1d.2/usb7/7-1/7-1:1.0/usb/hiddev0/device/driver -> ../../../../../../bus/usb/drivers/usbhid Signed-off-by: Guillaume Chazarain <guichaz@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-09-14x86, build: Disable -fPIE when compiling with CONFIG_CC_STACKPROTECTOR=ybasile@opensource.dyc.edu1-1/+1
The arch/x86/Makefile uses scripts/gcc-x86_$(BITS)-has-stack-protector.sh to check if cc1 supports -fstack-protector. When -fPIE is passed to cc1, these scripts fail causing stack protection to be disabled even when it is available. This fix is similar to commit c47efe5548abbf53c2f66e06dcb46183b11d6b22 Reported-by: Kai Dietrich <mail@cleeus.de> Signed-off-by: Magnus Granberg <zorry@gentoo.org> LKML-Reference: <20100913101319.748A1148E216@opensource.dyc.edu> Signed-off-by: Anthony G. Basile <basile@opensource.dyc.edu> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-09-13x86, cpufeature: Suppress compiler warning with gcc 3.xTetsuo Handa1-2/+2
Gcc 3.x generates a warning arch/x86/include/asm/cpufeature.h: In function `__static_cpu_has': arch/x86/include/asm/cpufeature.h:326: warning: asm operand 1 probably doesn't match constraints on each file. But static_cpu_has() for gcc 3.x does not need __static_cpu_has(). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> LKML-Reference: <201008300127.o7U1RC6Z044051@www262.sakura.ne.jp> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-09-13sound: Remove pr_<level> uses of KERN_<level>Joe Perches2-3/+2
Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Geoff Levand <geoff@infradead.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-09-13m68k,m68knommu: Wire up fanotify_init, fanotify_mark, and prlimit64Geert Uytterhoeven3-1/+10
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Greg Ungerer <gerg@uclinux.org>
2010-09-13sched: Improve latencies under load by decreasing minimum scheduling granularityIngo Molnar1-3/+3
Mathieu reported bad latencies with make -j10 kind of kbuild workloads - which is mostly caused by us scheduling with a too coarse granularity. Reduce the minimum granularity some more, to make sure we can meet the latency target. I got the following results (make -j10 kbuild load, average of 3 runs): vanilla: maximum latency: 38278.9 µs average latency: 7730.1 µs patched: maximum latency: 22702.1 µs average latency: 6684.8 µs Mathieu also measured it: | | * wakeup-latency.c (SIGEV_THREAD) with make -j10 | | - Mainline 2.6.35.2 kernel | | maximum latency: 45762.1 µs | average latency: 7348.6 µs | | - With only Peter's smaller min_gran (shown below): | | maximum latency: 29100.6 µs | average latency: 6684.1 µs | Reported-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <AANLkTi=8m4g01wZPacySoF7U0PevTNVgJoZZrHiUD-pN@mail.gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>