- 22 Aug, 2016 40 commits
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James Bottomley authored
commit a621bac3 upstream. When SCSI was written, all commands coming from the filesystem (REQ_TYPE_FS commands) had data. This meant that our signal for needing to complete the command was the number of bytes completed being equal to the number of bytes in the request. Unfortunately, with the advent of flush barriers, we can now get zero length REQ_TYPE_FS commands, which confuse this logic because they satisfy the condition every time. This means they never get retried even for retryable conditions, like UNIT ATTENTION because we complete them early assuming they're done. Fix this by special casing the early completion condition to recognise zero length commands with errors and let them drop through to the retry code. Reported-by:
Sebastian Parschauer <s.parschauer@gmx.de> Signed-off-by:
James E.J. Bottomley <jejb@linux.vnet.ibm.com> Tested-by:
Jack Wang <jinpu.wang@profitbricks.com> Signed-off-by:
Martin K. Petersen <martin.petersen@oracle.com> [bwh: Backported to 3.16: adjust context] Signed-off-by:
Ben Hutchings <ben@decadent.org.uk>
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Jason Wang authored
commit addf8fc4 upstream. We used to check dev->reg_state against NETREG_REGISTERED after each time we are woke up. But after commit 9e641bdc ("net-tun: restructure tun_do_read for better sleep/wakeup efficiency"), it uses skb_recv_datagram() which does not check dev->reg_state. This will result if we delete a tun/tap device after a process is blocked in the reading. The device will wait for the reference count which was held by that process for ever. Fixes this by using RCV_SHUTDOWN which will be checked during sk_recv_datagram() before trying to wake up the process during uninit. Fixes: 9e641bdc ("net-tun: restructure tun_do_read for better sleep/wakeup efficiency") Cc: Eric Dumazet <edumazet@google.com> Cc: Xi Wang <xii@google.com> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by:
Jason Wang <jasowang@redhat.com> Acked-by:
Eric Dumazet <edumazet@google.com> Acked-by:
Michael S. Tsirkin <mst@redhat.com> Signed-off-by:
David S. Miller <davem@davemloft.net> Signed-off-by:
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Rafael J. Wysocki authored
commit 3a17fb32 upstream. Grygorii Strashko reports: The PM runtime will be left disabled for the device if its .suspend_late() callback fails and async suspend is not allowed for this device. In this case device will not be added in dpm_late_early_list and dpm_resume_early() will ignore this device, as result PM runtime will be disabled for it forever (side effect: after 8 subsequent failures for the same device the PM runtime will be reenabled due to disable_depth overflow). To fix this problem, add devices to dpm_late_early_list regardless of whether or not device_suspend_late() returns errors for them. That will ensure failures in there to be handled consistently for all devices regardless of their async suspend/resume status. Reported-by:
Grygorii Strashko <grygorii.strashko@ti.com> Tested-by:
Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by:
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Ricky Liang authored
commit affa80bd upstream. When running a 32-bit userspace on a 64-bit kernel, the UI_SET_PHYS ioctl needs to be treated with special care, as it has the pointer size encoded in the command. Signed-off-by:
Ricky Liang <jcliang@chromium.org> Signed-off-by:
Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by:
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Sachin Prabhu authored
commit b74cb9a8 upstream. The session key is the default keyring set for request_key operations. This session key is revoked when the user owning the session logs out. Any long running daemon processes started by this session ends up with revoked session keyring which prevents these processes from using the request_key mechanism from obtaining the krb5 keys. The problem has been reported by a large number of autofs users. The problem is also seen with multiuser mounts where the share may be used by processes run by a user who has since logged out. A reproducer using automount is available on the Red Hat bz. The patch creates a new keyring which is used to cache cifs spnego upcalls. Red Hat bz: 1267754 Signed-off-by:
Sachin Prabhu <sprabhu@redhat.com> Reported-by:
Scott Mayhew <smayhew@redhat.com> Reviewed-by:
Shirish Pargaonkar <shirishpargaonkar@gmail.com> Signed-off-by:
Steve French <smfrench@gmail.com> [bwh: Backported to 3.16: keyring_alloc() doesn't take a restrict_link param] Signed-off-by:
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xypron.glpk@gmx.de authored
commit 1740c29a upstream. ehea_get_port may return NULL. Do not dereference NULL value. Fixes: 8c4877a4 ("ehea: Use the standard logging functions") Signed-off-by:
Heinrich Schuchardt <xypron.glpk@gmx.de> Acked-by:
Thadeu Lima de Souza Cascardo <cascardo@debian.org> Signed-off-by:
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Arnd Bergmann authored
commit bad6a185 upstream. In some rare randconfig builds, we can end up with ASYMMETRIC_PUBLIC_KEY_SUBTYPE enabled but CRYPTO_AKCIPHER disabled, which fails to link because of the reference to crypto_alloc_akcipher: crypto/built-in.o: In function `public_key_verify_signature': :(.text+0x110e4): undefined reference to `crypto_alloc_akcipher' This adds a Kconfig 'select' statement to ensure the dependency is always there. Signed-off-by:
Arnd Bergmann <arnd@arndb.de> Signed-off-by:
Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by:
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Dave Chinner authored
commit 7d3aa7fe upstream. We don't write back stale inodes so we should skip them in xfs_iflush_cluster, too. Signed-off-by:
Dave Chinner <dchinner@redhat.com> Reviewed-by:
Brian Foster <bfoster@redhat.com> Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Dave Chinner <david@fromorbit.com> Signed-off-by:
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Dave Chinner authored
commit 51b07f30 upstream. Some careless idiot(*) wrote crap code in commit 1a3e8f3d ("xfs: convert inode cache lookups to use RCU locking") back in late 2010, and so xfs_iflush_cluster checks the wrong inode for whether it is still valid under RCU protection. Fix it to lock and check the correct inode. (*) Careless-idiot: Dave Chinner <dchinner@redhat.com> Discovered-by:
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Dave Chinner authored
commit b1438f47 upstream. When a failure due to an inode buffer occurs, the error handling fails to abort the inode writeback correctly. This can result in the inode being reclaimed whilst still in the AIL, leading to use-after-free situations as well as filesystems that cannot be unmounted as the inode log items left in the AIL never get removed. Fix this by ensuring fatal errors from xfs_imap_to_bp() result in the inode flush being aborted correctly. Reported-by:
Shyam Kaushik <shyam@zadarastorage.com> Diagnosed-by:
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Sven Eckelmann authored
commit d285f52c upstream. The undefined behavior sanatizer detected an signed integer overflow in a setup with near perfect link quality UBSAN: Undefined behaviour in net/batman-adv/bat_iv_ogm.c:1246:25 signed integer overflow: 8713350 * 255 cannot be represented in type 'int' The problems happens because the calculation of mixed unsigned and signed integers resulted in an integer multiplication. batadv_ogm_packet::tq (u8 255) * tq_own (u8 255) * tq_asym_penalty (int 134; max 255) * tq_iface_penalty (int 255; max 255) The tq_iface_penalty, tq_asym_penalty and inv_asym_penalty can just be changed to unsigned int because they are not expected to become negative. Fixes: c0398768 ("batman-adv: add WiFi penalty") Signed-off-by:
Sven Eckelmann <sven.eckelmann@open-mesh.com> Signed-off-by:
Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by:
Antonio Quartulli <a@unstable.cc> [bwh: Backported to 3.16: adjust context] Signed-off-by:
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Sven Eckelmann authored
commit f7dcdf5f upstream. The function batadv_iv_ogm_orig_add_if allocates new buffers for bcast_own and bcast_own_sum. It is expected that these buffers are unchanged in case either bcast_own or bcast_own_sum couldn't be resized. But the error handling of this function frees the already resized buffer for bcast_own when the allocation of the new bcast_own_sum buffer failed. This will lead to an invalid memory access when some code will try to access bcast_own. Instead the resized new bcast_own buffer has to be kept. This will not lead to problems because the size of the buffer was only increased and therefore no user of the buffer will try to access bytes outside of the new buffer. Fixes: d0015fdd ("batman-adv: provide orig_node routing API") Signed-off-by:
Sven Eckelmann <sven@narfation.org> Signed-off-by:
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Florian Westphal authored
commit 63d443ef upstream. batadv_send_skb_to_orig() calls dev_queue_xmit() so we can't use skb->len. Fixes: 95332477 ("batman-adv: network coding - buffer unicast packets before forward") Signed-off-by:
Florian Westphal <fw@strlen.de> Reviewed-by:
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Daniel Lezcano authored
commit e7387da5 upstream. Commit 0b89e9aa (cpuidle: delay enabling interrupts until all coupled CPUs leave idle) rightfully fixed a regression by letting the coupled idle state framework to handle local interrupt enabling when the CPU is exiting an idle state. The current code checks if the idle state is coupled and, if so, it will let the coupled code to enable interrupts. This way, it can decrement the ready-count before handling the interrupt. This mechanism prevents the other CPUs from waiting for a CPU which is handling interrupts. But the check is done against the state index returned by the back end driver's ->enter functions which could be different from the initial index passed as parameter to the cpuidle_enter_state() function. entered_state = target_state->enter(dev, drv, index); [ ... ] if (!cpuidle_state_is_coupled(drv, entered_state)) local_irq_enable(); [ ... ] If the 'index' is referring to a coupled idle state but the 'entered_state' is *not* coupled, then the interrupts are enabled again. All CPUs blocked on the sync barrier may busy loop longer if the CPU has interrupts to handle before decrementing the ready-count. That's consuming more energy than saving. Fixes: 0b89e9aa (cpuidle: delay enabling interrupts until all coupled CPUs leave idle) Signed-off-by:
Daniel Lezcano <daniel.lezcano@linaro.org> [ rjw: Subject & changelog ] Signed-off-by:
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Chuck Lever authored
commit 4b9c7f9d upstream. Commit 176e21ee ("SUNRPC: Support for RPC over AF_LOCAL transports") added a 5-character netid, but did not bump RPCBIND_MAXNETIDLEN from 4 to 5. Fixes: 176e21ee ("SUNRPC: Support for RPC over AF_LOCAL ...") Signed-off-by:
Chuck Lever <chuck.lever@oracle.com> Signed-off-by:
Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by:
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Steve French authored
commit 897fba11 upstream. Wrong return code was being returned on SMB3 rmdir of non-empty directory. For SMB3 (unlike for cifs), we attempt to delete a directory by set of delete on close flag on the open. Windows clients set this flag via a set info (SET_FILE_DISPOSITION to set this flag) which properly checks if the directory is empty. With this patch on smb3 mounts we correctly return "DIRECTORY NOT EMPTY" on attempts to remove a non-empty directory. Signed-off-by:
Steve French <steve.french@primarydata.com> Acked-by:
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Stefan Metzmacher authored
commit 1a967d6c upstream. Only server which map unknown users to guest will allow access using a non-null NTLMv2_Response. For Samba it's the "map to guest = bad user" option. BUG: https://bugzilla.samba.org/show_bug.cgi?id=11913Signed-off-by:
Stefan Metzmacher <metze@samba.org> Signed-off-by:
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Stefan Metzmacher authored
commit 777f69b8 upstream. Only server which map unknown users to guest will allow access using a non-null NTChallengeResponse. For Samba it's the "map to guest = bad user" option. BUG: https://bugzilla.samba.org/show_bug.cgi?id=11913Signed-off-by:
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Stefan Metzmacher authored
commit fa8f3a35 upstream. Only server which map unknown users to guest will allow access using a non-null LMChallengeResponse. For Samba it's the "map to guest = bad user" option. BUG: https://bugzilla.samba.org/show_bug.cgi?id=11913Signed-off-by:
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Stefan Metzmacher authored
commit cfda35d9 upstream. See [MS-NLMP] 3.2.5.1.2 Server Receives an AUTHENTICATE_MESSAGE from the Client: ... Set NullSession to FALSE If (AUTHENTICATE_MESSAGE.UserNameLen == 0 AND AUTHENTICATE_MESSAGE.NtChallengeResponse.Length == 0 AND (AUTHENTICATE_MESSAGE.LmChallengeResponse == Z(1) OR AUTHENTICATE_MESSAGE.LmChallengeResponse.Length == 0)) -- Special case: client requested anonymous authentication Set NullSession to TRUE ... Only server which map unknown users to guest will allow access using a non-null NTChallengeResponse. For Samba it's the "map to guest = bad user" option. BUG: https://bugzilla.samba.org/show_bug.cgi?id=11913Signed-off-by:
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Lyude authored
commit 255f0e7c upstream. During boot, MST hotplugs are generally expected (even if no physical hotplugging occurs) and result in DRM's connector topology changing. This means that using num_connector from the current mode configuration can lead to the number of connectors changing under us. This can lead to some nasty scenarios in fbcon: - We allocate an array to the size of dev->mode_config.num_connectors. - MST hotplug occurs, dev->mode_config.num_connectors gets incremented. - We try to loop through each element in the array using the new value of dev->mode_config.num_connectors, and end up going out of bounds since dev->mode_config.num_connectors is now larger then the array we allocated. fb_helper->connector_count however, will always remain consistent while we do a modeset in fb_helper. Note: This is just polish for 4.7, Dave Airlie's drm_connector refcounting fixed these bugs for real. But it's good enough duct-tape for stable kernel backporting, since backporting the refcounting changes is way too invasive. Signed-off-by:
Lyude <cpaul@redhat.com> [danvet: Clarify why we need this. Also remove the now unused "dev" local variable to appease gcc.] Signed-off-by:
Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1463065021-18280-3-git-send-email-cpaul@redhat.comSigned-off-by:
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Lyude authored
commit 14a3842a upstream. During boot time, MST devices usually send a ton of hotplug events irregardless of whether or not any physical hotplugs actually occurred. Hotplugs mean connectors being created/destroyed, and the number of DRM connectors changing under us. This isn't a problem if we use fb_helper->connector_count since we only set it once in the code, however if we use num_connector from struct drm_mode_config we risk it's value changing under us. On top of that, there's even a chance that dev->mode_config.num_connector != fb_helper->connector_count. If the number of connectors happens to increase under us, we'll end up using the wrong array size for memcpy and start writing beyond the actual length of the array, occasionally resulting in kernel panics. Note: This is just polish for 4.7, Dave Airlie's drm_connector refcounting fixed these bugs for real. But it's good enough duct-tape for stable kernel backporting, since backporting the refcounting changes is way too invasive. Signed-off-by:
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Peter Zijlstra authored
commit 2e636d5e upstream. Vikram reported that his ARM64 compiler managed to 'optimize' away the preempt_count manipulations in code like: preempt_enable_no_resched(); put_user(); preempt_disable(); Irrespective of that fact that that is horrible code that should be fixed for many reasons, it does highlight a deficiency in the generic preempt_count manipulators. As it is never right to combine/elide preempt_count manipulations like this. Therefore sprinkle some volatile in the two generic accessors to ensure the compiler is aware of the fact that the preempt_count is observed outside of the regular program-order view and thus cannot be optimized away like this. x86; the only arch not using the generic code is not affected as we do all this in asm in order to use the segment base per-cpu stuff. Reported-by:
Vikram Mulukutla <markivx@codeaurora.org> Tested-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: a7878709 ("sched, arch: Create asm/preempt.h") Link: http://lkml.kernel.org/r/20160516131751.GH3205@twins.programming.kicks-ass.netSigned-off-by:
Ingo Molnar <mingo@kernel.org> [bwh: Backported to 3.16: use ACCESS_ONCE() instead of READ_ONCE()] Signed-off-by:
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Herbert Xu authored
commit 92964c79 upstream. When we free cb->skb after a dump, we do it after releasing the lock. This means that a new dump could have started in the time being and we'll end up freeing their skb instead of ours. This patch saves the skb and module before we unlock so we free the right memory. Fixes: 16b304f3 ("netlink: Eliminate kmalloc in netlink dump operation.") Reported-by:
Baozeng Ding <sploving1@gmail.com> Signed-off-by:
Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by:
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Prarit Bhargava authored
commit ad67b437 upstream. b84106b4 ("PCI: Disable IO/MEM decoding for devices with non-compliant BARs") disabled BAR sizing for BARs 0-5 of devices that don't comply with the PCI spec. But it didn't do anything for expansion ROM BARs, so we still try to size them, resulting in warnings like this on Broadwell-EP: pci 0000:ff:12.0: BAR 6: failed to assign [mem size 0x00000001 pref] Move the non-compliant BAR check from __pci_read_base() up to pci_read_bases() so it applies to the expansion ROM BAR as well as to BARs 0-5. Note that direct callers of __pci_read_base(), like sriov_init(), will now bypass this check. We haven't had reports of devices with broken SR-IOV BARs yet. [bhelgaas: changelog] Fixes: b84106b4 ("PCI: Disable IO/MEM decoding for devices with non-compliant BARs") Signed-off-by:
Prarit Bhargava <prarit@redhat.com> Signed-off-by:
Bjorn Helgaas <bhelgaas@google.com> CC: Thomas Gleixner <tglx@linutronix.de> CC: Ingo Molnar <mingo@redhat.com> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Andi Kleen <ak@linux.intel.com> Signed-off-by:
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Prarit Bhargava authored
commit da77b671 upstream. Commit b8941571 ("x86/PCI: Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs") marked Home Agent 0 & PCU has having non-compliant BARs. Home Agent 1 also has non-compliant BARs. Mark Home Agent 1 as having non-compliant BARs so the PCI core doesn't touch them. The problem with these devices is documented in the Xeon v4 specification update: BDF2 PCI BARs in the Home Agent Will Return Non-Zero Values During Enumeration Problem: During system initialization the Operating System may access the standard PCI BARs (Base Address Registers). Due to this erratum, accesses to the Home Agent BAR registers (Bus 1; Device 18; Function 0,4; Offsets (0x14-0x24) will return non-zero values. Implication: The operating system may issue a warning. Intel has not observed any functional failures due to this erratum. Link: http://www.intel.com/content/www/us/en/processors/xeon/xeon-e5-v4-spec-update.html Fixes: b8941571 ("x86/PCI: Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs") Signed-off-by:
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Tariq Toukan authored
commit 2bb07e15 upstream. Prevent using uninitialized or negative index when handling steering entries. Fixes: b12d93d6 ('mlx4: Add support for promiscuous mode in the new steering model.') Signed-off-by:
Tariq Toukan <tariqt@mellanox.com> Reported-by:
Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by:
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Bartlomiej Zolnierkiewicz authored
commit b3a834b1 upstream. When this_order variable in blk_mq_init_rq_map() becomes zero the code incorrectly decrements the variable and passes the result to order_to_size() helper causing undefined behaviour: UBSAN: Undefined behaviour in block/blk-mq.c:1459:27 shift exponent 4294967295 is too large for 32-bit type 'unsigned int' CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.6.0-rc6-00072-g33656a1f #22 Fix the code by checking this_order variable for not having the zero value first. Reported-by:
Meelis Roos <mroos@linux.ee> Fixes: 320ae51f ("blk-mq: new multi-queue block IO queueing mechanism") Signed-off-by:
Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by:
Jens Axboe <axboe@fb.com> Signed-off-by:
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Adrian Hunter authored
commit 1c447116 upstream. Some eMMCs set the partition switch timeout too low. Now typically eMMCs are considered a critical component (e.g. because they store the root file system) and consequently are expected to be reliable. Thus we can neglect the use case where eMMCs can't switch reliably and we might want a lower timeout to facilitate speedy recovery. Although we could employ a quirk for the cards that are affected (if we could identify them all), as described above, there is little benefit to having a low timeout, so instead simply set a minimum timeout. The minimum is set to 300ms somewhat arbitrarily - the examples that have been seen had a timeout of 10ms but were sometimes taking 60-70ms. Signed-off-by:
Adrian Hunter <adrian.hunter@intel.com> Signed-off-by:
Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by:
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Dan Carpenter authored
commit 1c306f7f upstream. We removed this initialization but it is required. Let's put it back. Fixes: 895106a5 ('i40e: trivial fixes') Signed-off-by:
Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by:
Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by:
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Mark Bloch authored
commit 2fa2d4fb upstream. Fix array overrun when going over callback table. In declaration of callback table, the max size isn't provided and in registration phase, it is provided. There is potential scenario where a new operation is added and it is not supported by current client. The acceptance of such operation by ib_netlink will cause to array overrun. Fixes: 809d5fc9 ("infiniband: pass rdma_cm module to netlink_dump_start") Fixes: b493d91d ("iwcm: common code for port mapper") Fixes: 2ca546b9 ("IB/sa: Route SA pathrecord query through netlink") Signed-off-by:
Mark Bloch <markb@mellanox.com> Reviewed-by:
Leon Romanovsky <leonro@mellanox.com> Signed-off-by:
Leon Romanovsky <leon@kernel.org> Signed-off-by:
Doug Ledford <dledford@redhat.com> [bwh: Backported to 3.16: - Only cma.c needs to be fixed - Adjust context] Signed-off-by:
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Mark Bloch authored
commit 5ed935e8 upstream. In case ibnl_put_msg fails in send_nlmsg_done, the function returns with -ENOMEM without freeing. This patch fixes this behavior. Fixes: 30dc5e63 ("RDMA/core: Add support for iWARP Port Mapper user space service") Signed-off-by:
Steve Wise <swise@opengridcomputing.com> Signed-off-by:
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Hariprasad S authored
commit 093108cb upstream. Currently c4iw_peer_abort_intr() does not wake up the waiter if the endpoint state indicates we're using MPAv2 and we're currently trying to connect. This was introduced with commit 7c0a33d6 ("RDMA/cxgb4: Don't wakeup threads for MPAv2") However, this original fix is flawed because it introduces a race that can cause a deadlock of the iwarp stack. Here is the race: ->local side sets up an active offload connection. ->local side sends MPA_START request. ->peer sends MPA_START response. ->local side ingress cpl thread begins processing the MPA_START response, but before it changes the state from MPA_REQ_SENT to FPDU_MODE: ->peer sends a RST which results in a ABORT_REQ_RSS. This triggers peer_abort_intr() which sees the state in MPA_REQ_SENT and since mpa_rev is 2, it will avoid waking up the endpoint with -ECONNRESET, assuming the stack will re-attempt the connection using MPAv1. ->Meanwhile, the cpl thread moves the state to FPDU_MODE and calls c4iw_modify_rc_qp() which calls rdma_init() which sends a RI_WR/INIT WR to firmware. But since HW sent an abort, FW correctly drops the RI_WR/INIT WR. ->So the cpl thread is stuck waiting for a reply and cannot process the ABORT_REQ_RSS cpl sitting in its input queue. Thus everything comes to a halt because no more ingress cpls are processed by the stack... The correct fix for the issue is to always do the wake up in c4iw_abort_intr() but reinitialize the wait object in c4iw_reconnect(). Fixes: 7c0a33d6 ("RDMA/cxgb4: Don't wakeup threads for MPAv2") Signed-off-by:
Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by:
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Steven Rostedt (Red Hat) authored
commit 59643d15 upstream. If the size passed to ring_buffer_resize() is greater than MAX_LONG - BUF_PAGE_SIZE then the DIV_ROUND_UP() will return zero. Here's the details: # echo 18014398509481980 > /sys/kernel/debug/tracing/buffer_size_kb tracing_entries_write() processes this and converts kb to bytes. 18014398509481980 << 10 = 18446744073709547520 and this is passed to ring_buffer_resize() as unsigned long size. size = DIV_ROUND_UP(size, BUF_PAGE_SIZE); Where DIV_ROUND_UP(a, b) is (a + b - 1)/b BUF_PAGE_SIZE is 4080 and here 18446744073709547520 + 4080 - 1 = 18446744073709551599 where 18446744073709551599 is still smaller than 2^64 2^64 - 18446744073709551599 = 17 But now 18446744073709551599 / 4080 = 4521260802379792 and size = size * 4080 = 18446744073709551360 This is checked to make sure its still greater than 2 * 4080, which it is. Then we convert to the number of buffer pages needed. nr_page = DIV_ROUND_UP(size, BUF_PAGE_SIZE) but this time size is 18446744073709551360 and 2^64 - (18446744073709551360 + 4080 - 1) = -3823 Thus it overflows and the resulting number is less than 4080, which makes 3823 / 4080 = 0 an nr_pages is set to this. As we already checked against the minimum that nr_pages may be, this causes the logic to fail as well, and we crash the kernel. There's no reason to have the two DIV_ROUND_UP() (that's just result of historical code changes), clean up the code and fix this bug. Fixes: 83f40318 ("ring-buffer: Make removal of ring buffer pages atomic") Signed-off-by:
Steven Rostedt <rostedt@goodmis.org> Signed-off-by:
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Steven Rostedt (Red Hat) authored
commit 9b94a8fb upstream. The size variable to change the ring buffer in ftrace is a long. The nr_pages used to update the ring buffer based on the size is int. On 64 bit machines this can cause an overflow problem. For example, the following will cause the ring buffer to crash: # cd /sys/kernel/debug/tracing # echo 10 > buffer_size_kb # echo 8556384240 > buffer_size_kb Then you get the warning of: WARNING: CPU: 1 PID: 318 at kernel/trace/ring_buffer.c:1527 rb_update_pages+0x22f/0x260 Which is: RB_WARN_ON(cpu_buffer, nr_removed); Note each ring buffer page holds 4080 bytes. This is because: 1) 10 causes the ring buffer to have 3 pages. (10kb requires 3 * 4080 pages to hold) 2) (2^31 / 2^10 + 1) * 4080 = 8556384240 The value written into buffer_size_kb is shifted by 10 and then passed to ring_buffer_resize(). 8556384240 * 2^10 = 8761737461760 3) The size passed to ring_buffer_resize() is then divided by BUF_PAGE_SIZE which is 4080. 8761737461760 / 4080 = 2147484672 4) nr_pages is subtracted from the current nr_pages (3) and we get: 2147484669. This value is saved in a signed integer nr_pages_to_update 5) 2147484669 is greater than 2^31 but smaller than 2^32, a signed int turns into the value of -2147482627 6) As the value is a negative number, in update_pages_handler() it is negated and passed to rb_remove_pages() and 2147482627 pages will be removed, which is much larger than 3 and it causes the warning because not all the pages asked to be removed were removed. Link: https://bugzilla.kernel.org/show_bug.cgi?id=118001 Fixes: 7a8e76a3 ("tracing: unified trace buffer") Reported-by:
Hao Qin <QEver.cn@gmail.com> Signed-off-by:
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Paul Burton authored
commit ab4a92e6 upstream. When emulating a jalr instruction with rd == $0, the code in isBranchInstr was incorrectly writing to GPR $0 which should actually always remain zeroed. This would lead to any further instructions emulated which use $0 operating on a bogus value until the task is next context switched, at which point the value of $0 in the task context would be restored to the correct zero by a store in SAVE_SOME. Fix this by not writing to rd if it is $0. Fixes: 102cedc3 ("MIPS: microMIPS: Floating point support.") Signed-off-by:
Paul Burton <paul.burton@imgtec.com> Cc: Maciej W. Rozycki <macro@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/13160/Signed-off-by:
Ralf Baechle <ralf@linux-mips.org> Signed-off-by:
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Lars Persson authored
commit 4d46a67a upstream. The lazy cache flushing implemented in the MIPS kernel suffers from a race condition that is exposed by do_set_pte() in mm/memory.c. A pre-condition is a file-system that writes to the page from the CPU in its readpage method and then calls flush_dcache_page(). One example is ubifs. Another pre-condition is that the dcache flush is postponed in __flush_dcache_page(). Upon a page fault for an executable mapping not existing in the page-cache, the following will happen: 1. Write to the page 2. flush_dcache_page 3. flush_icache_page 4. set_pte_at 5. update_mmu_cache (commits the flush of a dcache-dirty page) Between steps 4 and 5 another thread can hit the same page and it will encounter a valid pte. Because the data still is in the L1 dcache the CPU will fetch stale data from L2 into the icache and execute garbage. This fix moves the commit of the cache flush to step 3 to close the race window. It also reduces the amount of flushes on non-executable mappings because we never enter __flush_dcache_page() for non-aliasing CPUs. Regressions can occur in drivers that mistakenly relies on the flush_dcache_page() in get_user_pages() for DMA operations. [ralf@linux-mips.org: Folded in patch 9346 to fix highmem issue.] Signed-off-by:
Lars Persson <larper@axis.com> Cc: linux-mips@linux-mips.org Cc: paul.burton@imgtec.com Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/9346/ Patchwork: https://patchwork.linux-mips.org/patch/9738/Signed-off-by:
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Guilherme G. Piccoli authored
commit 8445a87f upstream. Commit 39baadbf ("powerpc/eeh: Remove eeh information from pci_dn") changed the pci_dn struct by removing its EEH-related members. As part of this clean-up, DDW mechanism was modified to read the device configuration address from eeh_dev struct. As a consequence, now if we disable EEH mechanism on kernel command-line for example, the DDW mechanism will fail, generating a kernel oops by dereferencing a NULL pointer (which turns to be the eeh_dev pointer). This patch just changes the configuration address calculation on DDW functions to a manual calculation based on pci_dn members instead of using eeh_dev-based address. No functional changes were made. This was tested on pSeries, both in PHyp and qemu guest. Fixes: 39baadbf ("powerpc/eeh: Remove eeh information from pci_dn") Reviewed-by:
Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by:
Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com> Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> Signed-off-by:
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Vik Heyndrickx authored
commit 20878232 upstream. Systems show a minimal load average of 0.00, 0.01, 0.05 even when they have no load at all. Uptime and /proc/loadavg on all systems with kernels released during the last five years up until kernel version 4.6-rc5, show a 5- and 15-minute minimum loadavg of 0.01 and 0.05 respectively. This should be 0.00 on idle systems, but the way the kernel calculates this value prevents it from getting lower than the mentioned values. Likewise but not as obviously noticeable, a fully loaded system with no processes waiting, shows a maximum 1/5/15 loadavg of 1.00, 0.99, 0.95 (multiplied by number of cores). Once the (old) load becomes 93 or higher, it mathematically can never get lower than 93, even when the active (load) remains 0 forever. This results in the strange 0.00, 0.01, 0.05 uptime values on idle systems. Note: 93/2048 = 0.0454..., which rounds up to 0.05. It is not correct to add a 0.5 rounding (=1024/2048) here, since the result from this function is fed back into the next iteration again, so the result of that +0.5 rounding value then gets multiplied by (2048-2037), and then rounded again, so there is a virtual "ghost" load created, next to the old and active load terms. By changing the way the internally kept value is rounded, that internal value equivalent now can reach 0.00 on idle, and 1.00 on full load. Upon increasing load, the internally kept load value is rounded up, when the load is decreasing, the load value is rounded down. The modified code was tested on nohz=off and nohz kernels. It was tested on vanilla kernel 4.6-rc5 and on centos 7.1 kernel 3.10.0-327. It was tested on single, dual, and octal cores system. It was tested on virtual hosts and bare hardware. No unwanted effects have been observed, and the problems that the patch intended to fix were indeed gone. Tested-by:
Damien Wyart <damien.wyart@free.fr> Signed-off-by:
Vik Heyndrickx <vik.heyndrickx@veribox.net> Signed-off-by:
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wang yanqing authored
commit 873ffe15 upstream. In commit a269913c ("rtlwifi: Rework rtl_lps_leave() and rtl_lps_enter() to use work queue"), the tests for enter/exit power-save mode were inverted. With this change applied, the wifi connection becomes much more stable. Fixes: a269913c ("rtlwifi: Rework rtl_lps_leave() and rtl_lps_enter() to use work queue") Signed-off-by:
Wang YanQing <udknight@gmail.com> Acked-by:
Larry Finger <Larry.Finger@lwfinger.net> Signed-off-by:
Kalle Valo <kvalo@codeaurora.org> [bwh: Backported to 3.16: - We only set a flag here to be used later, but it was also set the wrong way - Adjust filename] Signed-off-by:
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