summaryrefslogtreecommitdiff
AgeCommit message (Collapse)Author
2013-04-26Linux 3.8.10v3.8.10Greg Kroah-Hartman
2013-04-26Add file_ns_capable() helper function for open-time capability checkingLinus Torvalds
commit 935d8aabd4331f47a89c3e1daa5779d23cf244ee upstream. Nothing is using it yet, but this will allow us to delay the open-time checks to use time, without breaking the normal UNIX permission semantics where permissions are determined by the opener (and the file descriptor can then be passed to a different process, or the process can drop capabilities). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Shea Levy <shea@shealevy.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25Linux 3.8.9v3.8.9Greg Kroah-Hartman
2013-04-25Revert "MIPS: page.h: Provide more readable definition for PAGE_MASK."Ralf Baechle
commit 3b5e50edaf500f392f4a372296afc0b99ffa7e70 upstream. This reverts commit c17a6554782ad531f4713b33fd6339ba67ef6391. Manuel Lauss writes: lmo commit c17a6554 (MIPS: page.h: Provide more readable definition for PAGE_MASK) apparently breaks ioremap of 36-bit addresses on my Alchemy systems (PCI and PCMCIA) The reason is that in arch/mips/mm/ioremap.c line 157 (phys_addr &= PAGE_MASK) bits 32-35 are cut off. Seems the new PAGE_MASK is explicitly 32bit, or one could make it signed instead of unsigned long. From: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25s390: move dummy io_remap_pfn_range() to asm/pgtable.hLinus Torvalds
commit 4f2e29031e6c67802e7370292dd050fd62f337ee upstream. Commit b4cbb197c7e7 ("vm: add vm_iomap_memory() helper function") added a helper function wrapper around io_remap_pfn_range(), and every other architecture defined it in <asm/pgtable.h>. The s390 choice of <asm/io.h> may make sense, but is not very convenient for this case, and gratuitous differences like that cause unexpected errors like this: mm/memory.c: In function 'vm_iomap_memory': mm/memory.c:2439:2: error: implicit declaration of function 'io_remap_pfn_range' [-Werror=implicit-function-declaration] Glory be the kbuild test robot who noticed this, bisected it, and reported it to the guilty parties (ie me). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25Btrfs: make sure nbytes are right after log replayJosef Bacik
commit 4bc4bee4595662d8bff92180d5c32e3313a704b0 upstream. While trying to track down a tree log replay bug I noticed that fsck was always complaining about nbytes not being right for our fsynced file. That is because the new fsync stuff doesn't wait for ordered extents to complete, so the inodes nbytes are not necessarily updated properly when we log it. So to fix this we need to set nbytes to whatever it is on the inode that is on disk, so when we replay the extents we can just add the bytes that are being added as we replay the extent. This makes it work for the case that we have the wrong nbytes or the case that we logged everything and nbytes is actually correct. With this I'm no longer getting nbytes errors out of btrfsck. Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com> Signed-off-by: Lingzhu Xiang <lxiang@redhat.com> Reviewed-by: CAI Qian <caiqian@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25vm: convert mtdchar mmap to vm_iomap_memory() helperLinus Torvalds
commit 8558e4a26b00225efeb085725bc319f91201b239 upstream. This is my example conversion of a few existing mmap users. The mtdchar case is actually disabled right now (and stays disabled), but I did it because it showed up on my "git grep", and I was familiar with the code due to fixing an overflow problem in the code in commit 9c603e53d380 ("mtdchar: fix offset overflow detection"). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25vm: convert HPET mmap to vm_iomap_memory() helperLinus Torvalds
commit 2323036dfec8ce3ce6e1c86a49a31b039f3300d1 upstream. This is my example conversion of a few existing mmap users. The HPET case is simple, widely available, and easy to test (Clemens Ladisch sent a trivial test-program for it). Test-program-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25vm: convert fb_mmap to vm_iomap_memory() helperLinus Torvalds
commit fc9bbca8f650e5f738af8806317c0a041a48ae4a upstream. This is my example conversion of a few existing mmap users. The fb_mmap() case is a good example because it is a bit more complicated than some: fb_mmap() mmaps one of two different memory areas depending on the page offset of the mmap (but happily there is never any mixing of the two, so the helper function still works). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25vm: convert snd_pcm_lib_mmap_iomem() to vm_iomap_memory() helperLinus Torvalds
commit 0fe09a45c4848b5b5607b968d959fdc1821c161d upstream. This is my example conversion of a few existing mmap users. The pcm mmap case is one of the more straightforward ones. Acked-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25vm: add vm_iomap_memory() helper functionLinus Torvalds
commit b4cbb197c7e7a68dbad0d491242e3ca67420c13e upstream. Various drivers end up replicating the code to mmap() their memory buffers into user space, and our core memory remapping function may be very flexible but it is unnecessarily complicated for the common cases to use. Our internal VM uses pfn's ("page frame numbers") which simplifies things for the VM, and allows us to pass physical addresses around in a denser and more efficient format than passing a "phys_addr_t" around, and having to shift it up and down by the page size. But it just means that drivers end up doing that shifting instead at the interface level. It also means that drivers end up mucking around with internal VM things like the vma details (vm_pgoff, vm_start/end) way more than they really need to. So this just exports a function to map a certain physical memory range into user space (using a phys_addr_t based interface that is much more natural for a driver) and hides all the complexity from the driver. Some drivers will still end up tweaking the vm_page_prot details for things like prefetching or cacheability etc, but that's actually relevant to the driver, rather than caring about what the page offset of the mapping is into the particular IO memory region. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-25userns: Changing any namespace id mappings should require privilegesAndy Lutomirski
commit 41c21e351e79004dbb4efa4bc14a53a7e0af38c5 upstream. Changing uid/gid/projid mappings doesn't change your id within the namespace; it reconfigures the namespace. Unprivileged programs should *not* be able to write these files. (We're also checking the privileges on the wrong task.) Given the write-once nature of these files and the other security checks, this is likely impossible to usefully exploit. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25userns: Check uid_map's opener's fsuid, not the current fsuidAndy Lutomirski
commit e3211c120a85b792978bcb4be7b2886df18d27f0 upstream. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25userns: Don't let unprivileged users trick privileged users into setting the ↵Eric W. Biederman
id_map commit 6708075f104c3c9b04b23336bb0366ca30c3931b upstream. When we require privilege for setting /proc/<pid>/uid_map or /proc/<pid>/gid_map no longer allow an unprivileged user to open the file and pass it to a privileged program to write to the file. Instead when privilege is required require both the opener and the writer to have the necessary capabilities. I have tested this code and verified that setting /proc/<pid>/uid_map fails when an unprivileged user opens the file and a privielged user attempts to set the mapping, that unprivileged users can still map their own id, and that a privileged users can still setup an arbitrary mapping. Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25perf/x86: Fix offcore_rsp valid mask for SNB/IVBStephane Eranian
commit f1923820c447e986a9da0fc6bf60c1dccdf0408e upstream. The valid mask for both offcore_response_0 and offcore_response_1 was wrong for SNB/SNB-EP, IVB/IVB-EP. It was possible to write to reserved bit and cause a GP fault crashing the kernel. This patch fixes the problem by correctly marking the reserved bits in the valid mask for all the processors mentioned above. A distinction between desktop and server parts is introduced because bits 24-30 are only available on the server parts. This version of the patch is just a rebase to perf/urgent tree and should apply to older kernels as well. Signed-off-by: Stephane Eranian <eranian@google.com> Cc: peterz@infradead.org Cc: jolsa@redhat.com Cc: ak@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25perf: Treat attr.config as u64 in perf_swevent_init()Tommi Rantala
commit 8176cced706b5e5d15887584150764894e94e02f upstream. Trinity discovered that we fail to check all 64 bits of attr.config passed by user space, resulting to out-of-bounds access of the perf_swevent_enabled array in sw_perf_event_destroy(). Introduced in commit b0a873ebb ("perf: Register PMU implementations"). Signed-off-by: Tommi Rantala <tt.rantala@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: davej@redhat.com Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Link: http://lkml.kernel.org/r/1365882554-30259-1-git-send-email-tt.rantala@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25crypto: algif - suppress sending source address information in recvmsgMathias Krause
commit 72a763d805a48ac8c0bf48fdb510e84c12de51fe upstream. The current code does not set the msg_namelen member to 0 and therefore makes net/socket.c leak the local sockaddr_storage variable to userland -- 128 bytes of kernel stack memory. Fix that. Signed-off-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25ssb: implement spurious tone avoidanceRafał Miłecki
commit 46fc4c909339f5a84d1679045297d9d2fb596987 upstream. And make use of it in b43. This fixes a regression introduced with 49d55cef5b1925a5c1efb6aaddaa40fc7c693335 b43: N-PHY: implement spurious tone avoidance This commit made BCM4322 use only MCS 0 on channel 13, which of course resulted in performance drop (down to 0.7Mb/s). Reported-by: Stefan Brüns <stefan.bruens@rwth-aachen.de> Signed-off-by: Rafał Miłecki <zajec5@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25mac80211: fix cfg80211 interaction on auth/assoc requestJohannes Berg
commit 7b119dc06d871405fc7c3e9a73a6c987409ba639 upstream. If authentication (or association with FT) is requested by userspace, mac80211 currently doesn't tell cfg80211 that it disconnected from the AP. That leaves inconsistent state: cfg80211 thinks it's connected while mac80211 thinks it's not. Typically this won't last long, as soon as mac80211 reports the new association to cfg80211 the old one goes away. If, however, the new authentication or association doesn't succeed, then cfg80211 will forever think the old one still exists and will refuse attempts to authenticate or associate with the AP it thinks it's connected to. Anders reported that this leads to it taking a very long time to reconnect to a network, or never even succeeding. I tested this with an AP hacked to never respond to auth frames, and one that works, and with just those two the system never recovers because one won't work and cfg80211 thinks it's connected to the other so refuses connections to it. To fix this, simply make mac80211 tell cfg80211 when it is no longer connected to the old AP, while authenticating or associating to a new one. Reported-by: Anders Kaseorg <andersk@mit.edu> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25ath9k_hw: change AR9580 initvals to fix a stability issueFelix Fietkau
commit f09a878511997c25a76bf111a32f6b8345a701a5 upstream. The hardware parsing of Control Wrapper Frames needs to be disabled, as it has been causing spurious decryption error reports. The initvals for other chips have been updated to disable it, but AR9580 was left out for some reason. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25ath9k_htc: accept 1.x firmware newer than 1.3Felix Fietkau
commit 319e7bd96aca64a478f3aad40711c928405b8b77 upstream. Since the firmware has been open sourced, the minor version has been bumped to 1.4 and the API/ABI will stay compatible across further 1.x releases. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25ARM: 7698/1: perf: fix group validation when using enable_on_execWill Deacon
commit cb2d8b342aa084d1f3ac29966245dec9163677fb upstream. Events may be created with attr->disabled == 1 and attr->enable_on_exec == 1, which confuses the group validation code because events with the PERF_EVENT_STATE_OFF are not considered candidates for scheduling, which may lead to failure at group scheduling time. This patch fixes the validation check for ARM, so that events in the OFF state are still considered when enable_on_exec is true. Reported-by: Sudeep KarkadaNagesha <Sudeep.KarkadaNagesha@arm.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Cc: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25ARM: 7696/1: Fix kexec by setting outer_cache.inv_all for FeroceonIllia Ragozin
commit cd272d1ea71583170e95dde02c76166c7f9017e6 upstream. On Feroceon the L2 cache becomes non-coherent with the CPU when the L1 caches are disabled. Thus the L2 needs to be invalidated after both L1 caches are disabled. On kexec before the starting the code for relocation the kernel, the L1 caches are disabled in cpu_froc_fin (cpu_v7_proc_fin for Feroceon), but after L2 cache is never invalidated, because inv_all is not set in cache-feroceon-l2.c. So kernel relocation and decompression may has (and usually has) errors. Setting the function enables L2 invalidation and fixes the issue. Signed-off-by: Illia Ragozin <illia.ragozin@grapecom.com> Acked-by: Jason Cooper <jason@lakedaemon.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25sched/debug: Fix sd->*_idx limit range avoiding overflowlibin
commit fd9b86d37a600488dbd80fe60cca46b822bff1cd upstream. Commit 201c373e8e ("sched/debug: Limit sd->*_idx range on sysctl") was an incomplete bug fix. This patch fixes sd->*_idx limit range to [0 ~ CPU_LOAD_IDX_MAX-1] avoiding array overflow caused by setting sd->*_idx to CPU_LOAD_IDX_MAX on sysctl. Signed-off-by: Libin <huawei.libin@huawei.com> Cc: <jiang.liu@huawei.com> Cc: <guohanjun@huawei.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/51626610.2040607@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25sched: Convert BUG_ON()s in try_to_wake_up_local() to WARN_ON_ONCE()sTejun Heo
commit 383efcd00053ec40023010ce5034bd702e7ab373 upstream. try_to_wake_up_local() should only be invoked to wake up another task in the same runqueue and BUG_ON()s are used to enforce the rule. Missing try_to_wake_up_local() can stall workqueue execution but such stalls are likely to be finite either by another work item being queued or the one blocked getting unblocked. There's no reason to trigger BUG while holding rq lock crashing the whole system. Convert BUG_ON()s in try_to_wake_up_local() to WARN_ON_ONCE()s. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20130318192234.GD3042@htj.dyndns.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25tg3: Add 57766 device support.Matt Carlson
commit d3f677afb8076d09d090ff0a5d1229c9dd9f136e upstream. The patch also adds a couple of fixes - For the 57766 and non Ax versions of 57765, bootcode needs to setup the PCIE Fast Training Sequence (FTS) value to prevent transmit hangs. Unfortunately, it does not have enough room in the selfboot case (i.e. devices with no NVRAM). The driver needs to implement this. - For performance reasons, the 2k DMA engine mode on the 57766 should be enabled and dma size limited to 2k for standard sized packets. Signed-off-by: Nithin Nayak Sujir <nsujir@broadcom.com> Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Joseph Salisbury <joseph.salisbury@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25ARM: clk-imx35: Bugfix iomux clockMarkus Pargmann
commit cab1e0a36c9dd0b0671fb84197ed294513f5adc1 upstream. This patch enables iomuxc_gate clock. It is necessary to be able to reconfigure iomux pads. Without this clock enabled, the clk_disable_unused function will disable this clock and the iomux pads are not configurable anymore. This happens at every boot. After a reboot (watchdog system reset) the clock is not enabled again, so all iomux pad reconfigurations in boot code are without effect. The iomux pads should be always configurable, so this patch always enables it. Signed-off-by: Markus Pargmann <mpa@pengutronix.de> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Cc: Lingzhu Xiang <lxiang@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25ARM: i.MX35: enable MAX clockSascha Hauer
commit 5dc2eb7da1e387e31ce54f54af580c6a6f512ca6 upstream. The i.MX35 has two bits per clock gate which are decoded as follows: 0b00 -> clock off 0b01 -> clock is on in run mode, off in wait/doze 0b10 -> clock is on in run/wait mode, off in doze 0b11 -> clock is always on The reset value for the MAX clock is 0b10. The MAX clock is needed by the SoC, yet unused in the Kernel, so the common clock framework will disable it during late init time. It will only disable clocks though which it detects as being turned on. This detection is made depending on the lower bit of the gate. If the reset value has been altered by the bootloader to 0b11 the clock framework will detect the clock as turned on, yet unused, hence it will turn it off and the system locks up. This patch turns the MAX clock on unconditionally making the Kernel independent of the bootloader. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Cc: Lingzhu Xiang <lxiang@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25KVM: Allow cross page reads and writes from cached translations.Andrew Honig
commit 8f964525a121f2ff2df948dac908dcc65be21b5b upstream. This patch adds support for kvm_gfn_to_hva_cache_init functions for reads and writes that will cross a page. If the range falls within the same memslot, then this will be a fast operation. If the range is split between two memslots, then the slower kvm_read_guest and kvm_write_guest are used. Tested: Test against kvm_clock unit tests. Signed-off-by: Andrew Honig <ahonig@google.com> Signed-off-by: Gleb Natapov <gleb@redhat.com> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25KVM: Fix bounds checking in ioapic indirect register reads (CVE-2013-1798)Andy Honig
commit a2c118bfab8bc6b8bb213abfc35201e441693d55 upstream. If the guest specifies a IOAPIC_REG_SELECT with an invalid value and follows that with a read of the IOAPIC_REG_WINDOW KVM does not properly validate that request. ioapic_read_indirect contains an ASSERT(redir_index < IOAPIC_NUM_PINS), but the ASSERT has no effect in non-debug builds. In recent kernels this allows a guest to cause a kernel oops by reading invalid memory. In older kernels (pre-3.3) this allows a guest to read from large ranges of host memory. Tested: tested against apic unit tests. Signed-off-by: Andrew Honig <ahonig@google.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25KVM: x86: Convert MSR_KVM_SYSTEM_TIME to use gfn_to_hva_cache functions ↵Andy Honig
(CVE-2013-1797) commit 0b79459b482e85cb7426aa7da683a9f2c97aeae1 upstream. There is a potential use after free issue with the handling of MSR_KVM_SYSTEM_TIME. If the guest specifies a GPA in a movable or removable memory such as frame buffers then KVM might continue to write to that address even after it's removed via KVM_SET_USER_MEMORY_REGION. KVM pins the page in memory so it's unlikely to cause an issue, but if the user space component re-purposes the memory previously used for the guest, then the guest will be able to corrupt that memory. Tested: Tested against kvmclock unit test Signed-off-by: Andrew Honig <ahonig@google.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25KVM: x86: fix for buffer overflow in handling of MSR_KVM_SYSTEM_TIME ↵Andy Honig
(CVE-2013-1796) commit c300aa64ddf57d9c5d9c898a64b36877345dd4a9 upstream. If the guest sets the GPA of the time_page so that the request to update the time straddles a page then KVM will write onto an incorrect page. The write is done byusing kmap atomic to get a pointer to the page for the time structure and then performing a memcpy to that page starting at an offset that the guest controls. Well behaved guests always provide a 32-byte aligned address, however a malicious guest could use this to corrupt host kernel memory. Tested: Tested against kvmclock unit test. Signed-off-by: Andrew Honig <ahonig@google.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25md: raid1,10: Handle REQ_WRITE_SAME flag in write biosJoe Lawrence
commit c8dc9c654794a765ca61baed07f84ed8aaa7ca8c upstream. Set mddev queue's max_write_same_sectors to its chunk_sector value (before disk_stack_limits merges the underlying disk limits.) With that in place, be sure to handle writes coming down from the block layer that have the REQ_WRITE_SAME flag set. That flag needs to be copied into any newly cloned write bio. Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Acked-by: "Martin K. Petersen" <martin.petersen@oracle.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25hfsplus: fix potential overflow in hfsplus_file_truncate()Vyacheslav Dubeyko
commit 12f267a20aecf8b84a2a9069b9011f1661c779b4 upstream. Change a u32 to loff_t hfsplus_file_truncate(). Signed-off-by: Vyacheslav Dubeyko <slava@dubeyko.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Hin-Tak Leung <htl10@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25kernel/signal.c: stop info leak via the tkill and the tgkill syscallsEmese Revfy
commit b9e146d8eb3b9ecae5086d373b50fa0c1f3e7f0f upstream. This fixes a kernel memory contents leak via the tkill and tgkill syscalls for compat processes. This is visible in the siginfo_t->_sifields._rt.si_sigval.sival_ptr field when handling signals delivered from tkill. The place of the infoleak: int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from) { ... put_user_ex(ptr_to_compat(from->si_ptr), &to->si_ptr); ... } Signed-off-by: Emese Revfy <re.emese@gmail.com> Reviewed-by: PaX Team <pageexec@freemail.hu> Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25fs/binfmt_elf.c: fix hugetlb memory check in vma_dump_size()Naoya Horiguchi
commit 23d9e482136e31c9d287633a6e473daa172767c4 upstream. Documentation/filesystems/proc.txt says about coredump_filter bitmask, Note bit 0-4 doesn't effect any hugetlb memory. hugetlb memory are only effected by bit 5-6. However current code can go into the subsequent flag checks of bit 0-4 for vma(VM_HUGETLB). So this patch inserts 'return' and makes it work as written in the document. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reviewed-by: Rik van Riel <riel@redhat.com> Acked-by: Michal Hocko <mhocko@suse.cz> Reviewed-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-25hugetlbfs: add swap entry check in follow_hugetlb_page()Naoya Horiguchi
commit 9cc3a5bd40067b9a0fbd49199d0780463fc2140f upstream. With applying the previous patch "hugetlbfs: stop setting VM_DONTDUMP in initializing vma(VM_HUGETLB)" to reenable hugepage coredump, if a memory error happens on a hugepage and the affected processes try to access the error hugepage, we hit VM_BUG_ON(atomic_read(&page->_count) <= 0) in get_page(). The reason for this bug is that coredump-related code doesn't recognise "hugepage hwpoison entry" with which a pmd entry is replaced when a memory error occurs on a hugepage. In other words, physical address information is stored in different bit layout between hugepage hwpoison entry and pmd entry, so follow_hugetlb_page() which is called in get_dump_page() returns a wrong page from a given address. The expected behavior is like this: absent is_swap_pte FOLL_DUMP Expected behavior ------------------------------------------------------------------- true false false hugetlb_fault false true false hugetlb_fault false false false return page true false true skip page (to avoid allocation) false true true hugetlb_fault false false true return page With this patch, we can call hugetlb_fault() and take proper actions (we wait for migration entries, fail with VM_FAULT_HWPOISON_LARGE for hwpoisoned entries,) and as the result we can dump all hugepages except for hwpoisoned ones. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Rik van Riel <riel@redhat.com> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25hugetlbfs: stop setting VM_DONTDUMP in initializing vma(VM_HUGETLB)Naoya Horiguchi
commit a2fce9143057f4eb7675a21cca1b6beabe585c8b upstream. Currently we fail to include any data on hugepages into coredump, because VM_DONTDUMP is set on hugetlbfs's vma. This behavior was recently introduced by commit 314e51b9851b ("mm: kill vma flag VM_RESERVED and mm->reserved_vm counter"). This looks to me a serious regression, so let's fix it. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Acked-by: Michal Hocko <mhocko@suse.cz> Reviewed-by: Rik van Riel <riel@redhat.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25can: sja1000: fix handling on dt properties on little endian systemsChristoph Fritz
commit 0443de5fbf224abf41f688d8487b0c307dc5a4b4 upstream. To get correct endianes on little endian cpus (like arm) while reading device tree properties, this patch replaces of_get_property() with of_property_read_u32(). While there use of_property_read_bool() for the handling of the boolean "nxp,no-comparator-bypass" property. Signed-off-by: Christoph Fritz <chf.fritz@googlemail.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25can: mcp251x: add missing IRQF_ONESHOT to request_threaded_irqMarc Kleine-Budde
commit db388d6460ffa53b3b38429da6f70a913f89b048 upstream. Since commit: 1c6c695 genirq: Reject bogus threaded irq requests threaded irqs must provide a primary handler or set the IRQF_ONESHOT flag. Since the mcp251x driver doesn't make use of a primary handler set the IRQF_ONESHOT flag. Reported-by: Mylene Josserand <Mylene.Josserand@navocap.com> Tested-by: Mylene Josserand <Mylene.Josserand@navocap.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25hrtimer: Don't reinitialize a cpu_base lock on CPU_UPMichael Bohan
commit 84cc8fd2fe65866e49d70b38b3fdf7219dd92fe0 upstream. The current code makes the assumption that a cpu_base lock won't be held if the CPU corresponding to that cpu_base is offline, which isn't always true. If a hrtimer is not queued, then it will not be migrated by migrate_hrtimers() when a CPU is offlined. Therefore, the hrtimer's cpu_base may still point to a CPU which has subsequently gone offline if the timer wasn't enqueued at the time the CPU went down. Normally this wouldn't be a problem, but a cpu_base's lock is blindly reinitialized each time a CPU is brought up. If a CPU is brought online during the period that another thread is performing a hrtimer operation on a stale hrtimer, then the lock will be reinitialized under its feet, and a SPIN_BUG() like the following will be observed: <0>[ 28.082085] BUG: spinlock already unlocked on CPU#0, swapper/0/0 <0>[ 28.087078] lock: 0xc4780b40, value 0x0 .magic: dead4ead, .owner: <none>/-1, .owner_cpu: -1 <4>[ 42.451150] [<c0014398>] (unwind_backtrace+0x0/0x120) from [<c0269220>] (do_raw_spin_unlock+0x44/0xdc) <4>[ 42.460430] [<c0269220>] (do_raw_spin_unlock+0x44/0xdc) from [<c071b5bc>] (_raw_spin_unlock+0x8/0x30) <4>[ 42.469632] [<c071b5bc>] (_raw_spin_unlock+0x8/0x30) from [<c00a9ce0>] (__hrtimer_start_range_ns+0x1e4/0x4f8) <4>[ 42.479521] [<c00a9ce0>] (__hrtimer_start_range_ns+0x1e4/0x4f8) from [<c00aa014>] (hrtimer_start+0x20/0x28) <4>[ 42.489247] [<c00aa014>] (hrtimer_start+0x20/0x28) from [<c00e6190>] (rcu_idle_enter_common+0x1ac/0x320) <4>[ 42.498709] [<c00e6190>] (rcu_idle_enter_common+0x1ac/0x320) from [<c00e6440>] (rcu_idle_enter+0xa0/0xb8) <4>[ 42.508259] [<c00e6440>] (rcu_idle_enter+0xa0/0xb8) from [<c000f268>] (cpu_idle+0x24/0xf0) <4>[ 42.516503] [<c000f268>] (cpu_idle+0x24/0xf0) from [<c06ed3c0>] (rest_init+0x88/0xa0) <4>[ 42.524319] [<c06ed3c0>] (rest_init+0x88/0xa0) from [<c0c00978>] (start_kernel+0x3d0/0x434) As an example, this particular crash occurred when hrtimer_start() was executed on CPU #0. The code locked the hrtimer's current cpu_base corresponding to CPU #1. CPU #0 then tried to switch the hrtimer's cpu_base to an optimal CPU which was online. In this case, it selected the cpu_base corresponding to CPU #3. Before it could proceed, CPU #1 came online and reinitialized the spinlock corresponding to its cpu_base. Thus now CPU #0 held a lock which was reinitialized. When CPU #0 finally ended up unlocking the old cpu_base corresponding to CPU #1 so that it could switch to CPU #3, we hit this SPIN_BUG() above while in switch_hrtimer_base(). CPU #0 CPU #1 ---- ---- ... <offline> hrtimer_start() lock_hrtimer_base(base #1) ... init_hrtimers_cpu() switch_hrtimer_base() ... ... raw_spin_lock_init(&cpu_base->lock) raw_spin_unlock(&cpu_base->lock) ... <spin_bug> Solve this by statically initializing the lock. Signed-off-by: Michael Bohan <mbohan@codeaurora.org> Link: http://lkml.kernel.org/r/1363745965-23475-1-git-send-email-mbohan@codeaurora.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25kthread: Prevent unpark race which puts threads on the wrong cpuThomas Gleixner
commit f2530dc71cf0822f90bb63ea4600caaef33a66bb upstream. The smpboot threads rely on the park/unpark mechanism which binds per cpu threads on a particular core. Though the functionality is racy: CPU0 CPU1 CPU2 unpark(T) wake_up_process(T) clear(SHOULD_PARK) T runs leave parkme() due to !SHOULD_PARK bind_to(CPU2) BUG_ON(wrong CPU) We cannot let the tasks move themself to the target CPU as one of those tasks is actually the migration thread itself, which requires that it starts running on the target cpu right away. The solution to this problem is to prevent wakeups in park mode which are not from unpark(). That way we can guarantee that the association of the task to the target cpu is working correctly. Add a new task state (TASK_PARKED) which prevents other wakeups and use this state explicitly for the unpark wakeup. Peter noticed: Also, since the task state is visible to userspace and all the parked tasks are still in the PID space, its a good hint in ps and friends that these tasks aren't really there for the moment. The migration thread has another related issue. CPU0 CPU1 Bring up CPU2 create_thread(T) park(T) wait_for_completion() parkme() complete() sched_set_stop_task() schedule(TASK_PARKED) The sched_set_stop_task() call is issued while the task is on the runqueue of CPU1 and that confuses the hell out of the stop_task class on that cpu. So we need the same synchronizaion before sched_set_stop_task(). Reported-by: Dave Jones <davej@redhat.com> Reported-and-tested-by: Dave Hansen <dave@sr71.net> Reported-and-tested-by: Borislav Petkov <bp@alien8.de> Acked-by: Peter Ziljstra <peterz@infradead.org> Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: dhillf@gmail.com Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1304091635430.21884@ionos Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25ARM: Do 15e0d9e37c (ARM: pm: let platforms select cpu_suspend support) properlyRussell King
commit b6c7aabd923a17af993c5a5d5d7995f0b27c000a upstream. Let's do the changes properly and fix the same problem everywhere, not just for one case. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25kvm/powerpc/e500mc: fix tlb invalidation on cpu migrationScott Wood
commit c5e6cb051c5f7d56f05bd6a4af22cb300a4ced79 upstream. The existing check handles the case where we've migrated to a different core than we last ran on, but it doesn't handle the case where we're still on the same cpu we last ran on, but some other vcpu has run on this cpu in the meantime. Without this, guest segfaults (and other misbehavior) have been seen in smp guests. Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-25powerpc: add a missing label in resume_kernelKevin Hao
commit d8b92292408831d86ff7b781e66bf79301934b99 upstream. A label 0 was missed in the patch a9c4e541 (powerpc/kprobe: Complete kprobe and migrate exception frame). This will cause the kernel branch to an undetermined address if there really has a conflict when updating the thread flags. Signed-off-by: Kevin Hao <haokexin@gmail.com> Acked-By: Tiejun Chen <tiejun.chen@windriver.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-16Linux 3.8.8v3.8.8Greg Kroah-Hartman
2013-04-16tty: don't deadlock while flushing workqueueSebastian Andrzej Siewior
commit 852e4a8152b427c3f318bb0e1b5e938d64dcdc32 upstream. Since commit 89c8d91e31f2 ("tty: localise the lock") I see a dead lock in one of my dummy_hcd + g_nokia test cases. The first run was usually okay, the second often resulted in a splat by lockdep and the third was usually a dead lock. Lockdep complained about tty->hangup_work and tty->legacy_mutex taken both ways: | ====================================================== | [ INFO: possible circular locking dependency detected ] | 3.7.0-rc6+ #204 Not tainted | ------------------------------------------------------- | kworker/2:1/35 is trying to acquire lock: | (&tty->legacy_mutex){+.+.+.}, at: [<c14051e6>] tty_lock_nested+0x36/0x80 | | but task is already holding lock: | ((&tty->hangup_work)){+.+...}, at: [<c104f6e4>] process_one_work+0x124/0x5e0 | | which lock already depends on the new lock. | | the existing dependency chain (in reverse order) is: | | -> #2 ((&tty->hangup_work)){+.+...}: | [<c107fe74>] lock_acquire+0x84/0x190 | [<c104d82d>] flush_work+0x3d/0x240 | [<c12e6986>] tty_ldisc_flush_works+0x16/0x30 | [<c12e7861>] tty_ldisc_release+0x21/0x70 | [<c12e0dfc>] tty_release+0x35c/0x470 | [<c1105e28>] __fput+0xd8/0x270 | [<c1105fcd>] ____fput+0xd/0x10 | [<c1051dd9>] task_work_run+0xb9/0xf0 | [<c1002a51>] do_notify_resume+0x51/0x80 | [<c140550a>] work_notifysig+0x35/0x3b | | -> #1 (&tty->legacy_mutex/1){+.+...}: | [<c107fe74>] lock_acquire+0x84/0x190 | [<c140276c>] mutex_lock_nested+0x6c/0x2f0 | [<c14051e6>] tty_lock_nested+0x36/0x80 | [<c1405279>] tty_lock_pair+0x29/0x70 | [<c12e0bb8>] tty_release+0x118/0x470 | [<c1105e28>] __fput+0xd8/0x270 | [<c1105fcd>] ____fput+0xd/0x10 | [<c1051dd9>] task_work_run+0xb9/0xf0 | [<c1002a51>] do_notify_resume+0x51/0x80 | [<c140550a>] work_notifysig+0x35/0x3b | | -> #0 (&tty->legacy_mutex){+.+.+.}: | [<c107f3c9>] __lock_acquire+0x1189/0x16a0 | [<c107fe74>] lock_acquire+0x84/0x190 | [<c140276c>] mutex_lock_nested+0x6c/0x2f0 | [<c14051e6>] tty_lock_nested+0x36/0x80 | [<c140523f>] tty_lock+0xf/0x20 | [<c12df8e4>] __tty_hangup+0x54/0x410 | [<c12dfcb2>] do_tty_hangup+0x12/0x20 | [<c104f763>] process_one_work+0x1a3/0x5e0 | [<c104fec9>] worker_thread+0x119/0x3a0 | [<c1055084>] kthread+0x94/0xa0 | [<c140ca37>] ret_from_kernel_thread+0x1b/0x28 | |other info that might help us debug this: | |Chain exists of: | &tty->legacy_mutex --> &tty->legacy_mutex/1 --> (&tty->hangup_work) | | Possible unsafe locking scenario: | | CPU0 CPU1 | ---- ---- | lock((&tty->hangup_work)); | lock(&tty->legacy_mutex/1); | lock((&tty->hangup_work)); | lock(&tty->legacy_mutex); | | *** DEADLOCK *** Before the path mentioned tty_ldisc_release() look like this: | tty_ldisc_halt(tty); | tty_ldisc_flush_works(tty); | tty_lock(); As it can be seen, it first flushes the workqueue and then grabs the tty_lock. Now we grab the lock first: | tty_lock_pair(tty, o_tty); | tty_ldisc_halt(tty); | tty_ldisc_flush_works(tty); so lockdep's complaint seems valid. The earlier version of this patch took the ldisc_mutex since the other user of tty_ldisc_flush_works() (tty_set_ldisc()) did this. Peter Hurley then said that it is should not be requried. Since it wasn't done earlier, I dropped this part. The code under tty_ldisc_kill() was executed earlier with the tty lock taken so it is taken again. I was able to reproduce the deadlock on v3.8-rc1, this patch fixes the problem in my testcase. I didn't notice any problems so far. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Alan Cox <alan@linux.intel.com> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Bryan O'Donoghue <bryan.odonoghue.lkml@nexus-software.ie> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-16x86, mm: Patch out arch_flush_lazy_mmu_mode() when running on bare metalBoris Ostrovsky
commit 511ba86e1d386f671084b5d0e6f110bb30b8eeb2 upstream. Invoking arch_flush_lazy_mmu_mode() results in calls to preempt_enable()/disable() which may have performance impact. Since lazy MMU is not used on bare metal we can patch away arch_flush_lazy_mmu_mode() so that it is never called in such environment. [ hpa: the previous patch "Fix vmalloc_fault oops during lazy MMU updates" may cause a minor performance regression on bare metal. This patch resolves that performance regression. It is somewhat unclear to me if this is a good -stable candidate. ] Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: http://lkml.kernel.org/r/1364045796-10720-2-git-send-email-konrad.wilk@oracle.com Tested-by: Josh Boyer <jwboyer@redhat.com> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-16x86, mm, paravirt: Fix vmalloc_fault oops during lazy MMU updatesSamu Kallio
commit 1160c2779b826c6f5c08e5cc542de58fd1f667d5 upstream. In paravirtualized x86_64 kernels, vmalloc_fault may cause an oops when lazy MMU updates are enabled, because set_pgd effects are being deferred. One instance of this problem is during process mm cleanup with memory cgroups enabled. The chain of events is as follows: - zap_pte_range enables lazy MMU updates - zap_pte_range eventually calls mem_cgroup_charge_statistics, which accesses the vmalloc'd mem_cgroup per-cpu stat area - vmalloc_fault is triggered which tries to sync the corresponding PGD entry with set_pgd, but the update is deferred - vmalloc_fault oopses due to a mismatch in the PUD entries The OOPs usually looks as so: ------------[ cut here ]------------ kernel BUG at arch/x86/mm/fault.c:396! invalid opcode: 0000 [#1] SMP .. snip .. CPU 1 Pid: 10866, comm: httpd Not tainted 3.6.10-4.fc18.x86_64 #1 RIP: e030:[<ffffffff816271bf>] [<ffffffff816271bf>] vmalloc_fault+0x11f/0x208 .. snip .. Call Trace: [<ffffffff81627759>] do_page_fault+0x399/0x4b0 [<ffffffff81004f4c>] ? xen_mc_extend_args+0xec/0x110 [<ffffffff81624065>] page_fault+0x25/0x30 [<ffffffff81184d03>] ? mem_cgroup_charge_statistics.isra.13+0x13/0x50 [<ffffffff81186f78>] __mem_cgroup_uncharge_common+0xd8/0x350 [<ffffffff8118aac7>] mem_cgroup_uncharge_page+0x57/0x60 [<ffffffff8115fbc0>] page_remove_rmap+0xe0/0x150 [<ffffffff8115311a>] ? vm_normal_page+0x1a/0x80 [<ffffffff81153e61>] unmap_single_vma+0x531/0x870 [<ffffffff81154962>] unmap_vmas+0x52/0xa0 [<ffffffff81007442>] ? pte_mfn_to_pfn+0x72/0x100 [<ffffffff8115c8f8>] exit_mmap+0x98/0x170 [<ffffffff810050d9>] ? __raw_callee_save_xen_pmd_val+0x11/0x1e [<ffffffff81059ce3>] mmput+0x83/0xf0 [<ffffffff810624c4>] exit_mm+0x104/0x130 [<ffffffff8106264a>] do_exit+0x15a/0x8c0 [<ffffffff810630ff>] do_group_exit+0x3f/0xa0 [<ffffffff81063177>] sys_exit_group+0x17/0x20 [<ffffffff8162bae9>] system_call_fastpath+0x16/0x1b Calling arch_flush_lazy_mmu_mode immediately after set_pgd makes the changes visible to the consistency checks. RedHat-Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=914737 Tested-by: Josh Boyer <jwboyer@redhat.com> Reported-and-Tested-by: Krishna Raman <kraman@redhat.com> Signed-off-by: Samu Kallio <samu.kallio@aberdeencloud.com> Link: http://lkml.kernel.org/r/1364045796-10720-1-git-send-email-konrad.wilk@oracle.com Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-16sched_clock: Prevent 64bit inatomicity on 32bit systemsThomas Gleixner
commit a1cbcaa9ea87b87a96b9fc465951dcf36e459ca2 upstream. The sched_clock_remote() implementation has the following inatomicity problem on 32bit systems when accessing the remote scd->clock, which is a 64bit value. CPU0 CPU1 sched_clock_local() sched_clock_remote(CPU0) ... remote_clock = scd[CPU0]->clock read_low32bit(scd[CPU0]->clock) cmpxchg64(scd->clock,...) read_high32bit(scd[CPU0]->clock) While the update of scd->clock is using an atomic64 mechanism, the readout on the remote cpu is not, which can cause completely bogus readouts. It is a quite rare problem, because it requires the update to hit the narrow race window between the low/high readout and the update must go across the 32bit boundary. The resulting misbehaviour is, that CPU1 will see the sched_clock on CPU1 ~4 seconds ahead of it's own and update CPU1s sched_clock value to this bogus timestamp. This stays that way due to the clamping implementation for about 4 seconds until the synchronization with CLOCK_MONOTONIC undoes the problem. The issue is hard to observe, because it might only result in a less accurate SCHED_OTHER timeslicing behaviour. To create observable damage on realtime scheduling classes, it is necessary that the bogus update of CPU1 sched_clock happens in the context of an realtime thread, which then gets charged 4 seconds of RT runtime, which results in the RT throttler mechanism to trigger and prevent scheduling of RT tasks for a little less than 4 seconds. So this is quite unlikely as well. The issue was quite hard to decode as the reproduction time is between 2 days and 3 weeks and intrusive tracing makes it less likely, but the following trace recorded with trace_clock=global, which uses sched_clock_local(), gave the final hint: <idle>-0 0d..30 400269.477150: hrtimer_cancel: hrtimer=0xf7061e80 <idle>-0 0d..30 400269.477151: hrtimer_start: hrtimer=0xf7061e80 ... irq/20-S-587 1d..32 400273.772118: sched_wakeup: comm= ... target_cpu=0 <idle>-0 0dN.30 400273.772118: hrtimer_cancel: hrtimer=0xf7061e80 What happens is that CPU0 goes idle and invokes sched_clock_idle_sleep_event() which invokes sched_clock_local() and CPU1 runs a remote wakeup for CPU0 at the same time, which invokes sched_remote_clock(). The time jump gets propagated to CPU0 via sched_remote_clock() and stays stale on both cores for ~4 seconds. There are only two other possibilities, which could cause a stale sched clock: 1) ktime_get() which reads out CLOCK_MONOTONIC returns a sporadic wrong value. 2) sched_clock() which reads the TSC returns a sporadic wrong value. #1 can be excluded because sched_clock would continue to increase for one jiffy and then go stale. #2 can be excluded because it would not make the clock jump forward. It would just result in a stale sched_clock for one jiffy. After quite some brain twisting and finding the same pattern on other traces, sched_clock_remote() remained the only place which could cause such a problem and as explained above it's indeed racy on 32bit systems. So while on 64bit systems the readout is atomic, we need to verify the remote readout on 32bit machines. We need to protect the local->clock readout in sched_clock_remote() on 32bit as well because an NMI could hit between the low and the high readout, call sched_clock_local() and modify local->clock. Thanks to Siegfried Wulsch for bearing with my debug requests and going through the tedious tasks of running a bunch of reproducer systems to generate the debug information which let me decode the issue. Reported-by: Siegfried Wulsch <Siegfried.Wulsch@rovema.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1304051544160.21884@ionos Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
generated by cgit v1.2.3 (git 2.0.4) at 2025-04-23 03:18:16 +0000