- 16 Mar, 2016 40 commits
-
-
Linus Torvalds authored
commit 39680f50 upstream. The exit path will do some final updates to the VM of an exiting process to inform others of the fact that the process is going away. That happens, for example, for robust futex state cleanup, but also if the parent has asked for a TID update when the process exits (we clear the child tid field in user space). However, at the time we do those final VM accesses, we've already stopped accepting signals, so the usual "stop waiting for userfaults on signal" code in fs/userfaultfd.c no longer works, and the process can become an unkillable zombie waiting for something that will never happen. To solve this, just make handle_userfault() abort any user fault handling if we're already in the exit path past the signal handling state being dead (marked by PF_EXITING). This VM special case is pretty ugly, and it is possible that we should look at finalizing signals later (or move the VM final accesses earlier). But in the meantime this is a fairly minimally intrusive fix. Reported-and-tested-by:
Dmitry Vyukov <dvyukov@google.com> Acked-by:
Andrea Arcangeli <aarcange@redhat.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Cc: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Russell Currey authored
commit c88c5d43 upstream. The recently added OPAL API call, OPAL_CONSOLE_FLUSH, originally took no parameters and returned nothing. The call was updated to accept the terminal number to flush, and returned various values depending on the state of the output buffer. The prototype has been updated and its usage in the OPAL kmsg dumper has been modified to support its new behaviour as an incremental flush. Signed-off-by:
Russell Currey <ruscur@russell.cc> Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> Signed-off-by:
-
Russell Currey authored
commit affddff6 upstream. On BMC machines, console output is controlled by the OPAL firmware and is only flushed when its pollers are called. When the kernel is in a panic state, it no longer calls these pollers and thus console output does not completely flush, causing some output from the panic to be lost. Output is only actually lost when the kernel is configured to not power off or reboot after panic (i.e. CONFIG_PANIC_TIMEOUT is set to 0) since OPAL flushes the console buffer as part of its power down routines. Before this patch, however, only partial output would be printed during the timeout wait. This patch adds a new kmsg_dumper which gets called at panic time to ensure panic output is not lost. It accomplishes this by calling OPAL_CONSOLE_FLUSH in the OPAL API, and if that is not available, the pollers are called enough times to (hopefully) completely flush the buffer. The flushing mechanism will only affect output printed at and before the kmsg_dump call in kernel/panic.c:panic(). As such, the "end Kernel panic" message may still be truncated as follows: >Call Trace: >[c000000f1f603b00] [c0000000008e9458] dump_stack+0x90/0xbc (unreliable) >[c000000f1f603b30] [c0000000008e7e78] panic+0xf8/0x2c4 >[c000000f1f603bc0] [c000000000be4860] mount_block_root+0x288/0x33c >[c000000f1f603c80] [c000000000be4d14] prepare_namespace+0x1f4/0x254 >[c000000f1f603d00] [c000000000be43e8] kernel_init_freeable+0x318/0x350 >[c000000f1f603dc0] [c00000000000bd74] kernel_init+0x24/0x130 >[c000000f1f603e30] [c0000000000095b0] ret_from_kernel_thread+0x5c/0xac >---[ end Kernel panic - not This functionality is implemented as a kmsg_dumper as it seems to be the most sensible way to introduce platform-specific functionality to the panic function. Signed-off-by:
Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by:
-
Andreas Schwab authored
commit f15838e9 upstream. Since binutils 2.26 BFD is doing suffix merging on STRTAB sections. But dedotify modifies the symbol names in place, which can also modify unrelated symbols with a name that matches a suffix of a dotted name. To remove the leading dot of a symbol name we can just increment the pointer into the STRTAB section instead. Backport to all stables to avoid breakage when people update their binutils - mpe. Signed-off-by:
Andreas Schwab <schwab@linux-m68k.org> Signed-off-by:
-
Alex Deucher authored
commit d74e766e upstream. This reverts commit 39d42750. This caused a regression on some older hardware. bug: https://bugzilla.kernel.org/show_bug.cgi?id=113891Signed-off-by:
Alex Deucher <alexander.deucher@amd.com> Signed-off-by:
-
Mario Kleiner authored
commit 1e1490a3 upstream. This is a port of the patch "drm/amdgpu: Fix error handling in amdgpu_flip_work_func." to fix the following problem for radeon as well which was reported against amdgpu: The patch e1d09dc0: "drm/amdgpu: Don't hang in amdgpu_flip_work_func on disabled crtc." from Feb 19, 2016, leads to the following static checker warning, as reported by Dan Carpenter in https://lists.freedesktop.org/archives/dri-devel/2016-February/101987.html drivers/gpu/drm/amd/amdgpu/amdgpu_display.c:127 amdgpu_flip_work_func() warn: should this be 'repcnt == -1' drivers/gpu/drm/amd/amdgpu/amdgpu_display.c:136 amdgpu_flip_work_func() error: double unlock 'spin_lock:&crtc->dev->event_lock' drivers/gpu/drm/amd/amdgpu/amdgpu_display.c:136 amdgpu_flip_work_func() error: double unlock 'irqsave:flags' This patch fixes both reported problems: Change post-decrement of repcnt to pre-decrement, so it can't underflow anymore, but still performs up to three repetitions - three is the maximum one could expect in practice. Move the spin_unlock_irqrestore to where it actually belongs. Reviewed-by:
Michel Dänzer <michel.daenzer@amd.com> Reported-by:
Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by:
Mario Kleiner <mario.kleiner.de@gmail.com> Cc: Michel Dänzer <michel.daenzer@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Signed-off-by:
-
Mario Kleiner authored
commit 90e94b16 upstream. The patch e1d09dc0: "drm/amdgpu: Don't hang in amdgpu_flip_work_func on disabled crtc." from Feb 19, 2016, leads to the following static checker warning, as reported by Dan Carpenter in https://lists.freedesktop.org/archives/dri-devel/2016-February/101987.html drivers/gpu/drm/amd/amdgpu/amdgpu_display.c:127 amdgpu_flip_work_func() warn: should this be 'repcnt == -1' drivers/gpu/drm/amd/amdgpu/amdgpu_display.c:136 amdgpu_flip_work_func() error: double unlock 'spin_lock:&crtc->dev->event_lock' drivers/gpu/drm/amd/amdgpu/amdgpu_display.c:136 amdgpu_flip_work_func() error: double unlock 'irqsave:flags' This patch fixes both reported problems: Change post-decrement of repcnt to pre-decrement, so it can't underflow anymore, but still performs up to three repetitions - three is the maximum one could expect in practice. Move the spin_unlock_irqrestore to where it actually belongs. Reviewed-by:
-
Linus Torvalds authored
commit 256faedc upstream. This reverts commit dbb17a21. It turns out that commit can cause problems for systems with multiple GPUs, and causes X to hang on at least a HP Pavilion dv7 with hybrid graphics. This got noticed originally in 4.4.4, where this patch had already gotten back-ported, but 4.5-rc7 was verified to have the same problem. Alexander Deucher says: "It looks like you have a muxed system so I suspect what's happening is that one of the display is being reported as connected for both the IGP and the dGPU and then the desktop environment gets confused or there some sort problem in the detect functions since the mux is not switched to the dGPU. I don't see an easy fix unless Dave has any ideas. I'd say just revert for now" Reported-by:
Jörg-Volker Peetz <jvpeetz@web.de> Acked-by:
-
Dexuan Cui authored
commit bf70e551 upstream. "d1cd1210: x86, pageattr: Prevent overflow in slow_virt_to_phys() for X86_PAE" was unintentionally removed by the recent "34437e67: x86/mm: Fix slow_virt_to_phys() to handle large PAT bit". And, the variable 'phys_addr' was defined as "unsigned long" by mistake -- it should be "phys_addr_t". As a result, Hyper-V network driver in 32-PAE Linux guest can't work again. Fixes: commit 34437e67: "x86/mm: Fix slow_virt_to_phys() to handle large PAT bit" Signed-off-by:
Dexuan Cui <decui@microsoft.com> Reviewed-by:
Toshi Kani <toshi.kani@hpe.com> Cc: olaf@aepfle.de Cc: jasowang@redhat.com Cc: driverdev-devel@linuxdriverproject.org Cc: linux-mm@kvack.org Cc: apw@canonical.com Cc: Andrew Morton <akpm@linux-foundation.org> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Link: http://lkml.kernel.org/r/1456394292-9030-1-git-send-email-decui@microsoft.comSigned-off-by:
Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
-
Philipp Zabel authored
commit 17e05217 upstream. The port nodes are documented as optional, treat them accordingly. Reported-by:
Martin Fuzzey <mfuzzey@parkeon.com> Reported-by:
Chris Healy <Chris.Healy@zii.aero> Signed-off-by:
Philipp Zabel <p.zabel@pengutronix.de> Fixes: 304e6be6 ("gpu: ipu-v3: Assign of_node of child platform devices to corresponding ports") Signed-off-by:
-
Jouni Malinen authored
commit 1ec7bae8 upstream. Public Action frames use special rules for how the BSSID field (Address 3) is set. A wildcard BSSID is used in cases where the transmitter and recipient are not members of the same BSS. As such, we need to accept Public Action frames with wildcard BSSID. Commit db8e1732 ("mac80211: ignore frames between TDLS peers when operating as AP") added a rule that drops Action frames to TDLS-peers based on an Action frame having different DA (Address 1) and BSSID (Address 3) values. This is not correct since it misses the possibility of BSSID being a wildcard BSSID in which case the Address 1 would not necessarily match. Fix this by allowing mac80211 to accept wildcard BSSID in an Action frame when in AP mode. Fixes: db8e1732 ("mac80211: ignore frames between TDLS peers when operating as AP") Signed-off-by:
Jouni Malinen <jouni@qca.qualcomm.com> Signed-off-by:
Johannes Berg <johannes.berg@intel.com> Signed-off-by:
-
Johannes Berg authored
commit 9acc54be upstream. Just like for CCMP we need to check that for GCMP the fragments have PNs that increment by one; the spec was updated to fix this security issue and now has the following text: The receiver shall discard MSDUs and MMPDUs whose constituent MPDU PN values are not incrementing in steps of 1. Adapt the code for CCMP to work for GCMP as well, luckily the relevant fields already alias each other so no code duplication is needed (just check the aliasing with BUILD_BUG_ON.) Signed-off-by:
-
Felix Fietkau authored
commit c36dd3ea upstream. RTS/CTS needs to be enabled if the rate is a fallback rate *or* if it's a dual-stream rate and the sta is in dynamic SMPS mode. Fixes: a3ebb4e1 ("mac80211: minstrel_ht: handle peers in dynamic SMPS") Reported-by:
Matías Richart <mrichart@fing.edu.uy> Signed-off-by:
Felix Fietkau <nbd@openwrt.org> Signed-off-by:
-
Felix Fietkau authored
commit 7a36b930 upstream. The value 5000 was put here with the addition of the timeout field to ieee80211_start_tx_ba_session. It was originally added in mac80211 to save resources for drivers like iwlwifi, which only supports a limited number of concurrent aggregation sessions. Since iwlwifi does not use minstrel_ht and other drivers don't need this, 0 is a better default - especially since there have been recent reports of aggregation setup related issues reproduced with ath9k. This should improve stability without causing any adverse effects. Acked-by:
Avery Pennarun <apenwarr@gmail.com> Signed-off-by:
-
Chris Bainbridge authored
commit f39ea269 upstream. Use kzalloc instead of kmalloc for struct tid_ampdu_rx to initialize the "removed" field (all others are initialized manually). That fixes: UBSAN: Undefined behaviour in net/mac80211/rx.c:932:29 load of value 2 is not a valid value for type '_Bool' CPU: 3 PID: 1134 Comm: kworker/u16:7 Not tainted 4.5.0-rc1+ #265 Workqueue: phy0 rt2x00usb_work_rxdone 0000000000000004 ffff880254a7ba50 ffffffff8181d866 0000000000000007 ffff880254a7ba78 ffff880254a7ba68 ffffffff8188422d ffffffff8379b500 ffff880254a7bab8 ffffffff81884747 0000000000000202 0000000348620032 Call Trace: [<ffffffff8181d866>] dump_stack+0x45/0x5f [<ffffffff8188422d>] ubsan_epilogue+0xd/0x40 [<ffffffff81884747>] __ubsan_handle_load_invalid_value+0x67/0x70 [<ffffffff82227b4d>] ieee80211_sta_reorder_release.isra.16+0x5ed/0x730 [<ffffffff8222ca14>] ieee80211_prepare_and_rx_handle+0xd04/0x1c00 [<ffffffff8222db03>] __ieee80211_rx_handle_packet+0x1f3/0x750 [<ffffffff8222e4a7>] ieee80211_rx_napi+0x447/0x990 While at it, convert to use sizeof(*tid_agg_rx) instead. Fixes: 788211d8 ("mac80211: fix RX A-MPDU session reorder timer deletion") Signed-off-by:
Chris Bainbridge <chris.bainbridge@gmail.com> [reword commit message, use sizeof(*tid_agg_rx)] Signed-off-by:
-
Sven Eckelmann authored
commit 212c5a5e upstream. The change from cur_tp to the function minstrel_get_tp_avg/minstrel_ht_get_tp_avg changed the unit used for the current throughput. For example in minstrel_ht the correct conversion between them would be: mrs->cur_tp / 10 == minstrel_ht_get_tp_avg(..). This factor 10 must also be included in the calculation of minstrel_get_expected_throughput and minstrel_ht_get_expected_throughput to return values with the unit [Kbps] instead of [10Kbps]. Otherwise routing algorithms like B.A.T.M.A.N. V will make incorrect decision based on these values. Its kernel based implementation expects expected_throughput always to have the unit [Kbps] and not sometimes [10Kbps] and sometimes [Kbps]. The same requirement has iw or olsrdv2's nl80211 based statistics module which retrieve the same data via NL80211_STA_INFO_TX_BITRATE. Fixes: 6a27b2c4 ("mac80211: restructure per-rate throughput calculation into function") Signed-off-by:
Sven Eckelmann <sven@open-mesh.com> Signed-off-by:
-
Liad Kaufman authored
commit fb896c44 upstream. Until this patch, when TXing non-sta the pending_frames counter wasn't increased, but it WAS decreased in iwl_mvm_rx_tx_cmd_single(), what makes it negative in certain conditions. This in turn caused much trouble when we need to remove the station since we won't be waiting forever until pending_frames gets 0. In certain cases, we were exhausting the station table even in BSS mode, because we had a lot of stale stations. Increase the counter also in iwl_mvm_tx_skb_non_sta() after a successful TX to avoid this outcome. Signed-off-by:
Liad Kaufman <liad.kaufman@intel.com> Signed-off-by:
Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by:
-
Maximilain Schneider authored
commit e9a2d81b upstream. gs_destroy_candev() erroneously calls kfree() on a struct gs_can *, which is allocated through alloc_candev() and should instead be freed using free_candev() alone. The inappropriate use of kfree() causes the kernel to hang when gs_destroy_candev() is called. Only the struct gs_usb * which is allocated through kzalloc() should be freed using kfree() when the device is disconnected. Signed-off-by:
Maximilian Schneider <max@schneidersoft.net> Signed-off-by:
Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by:
-
Johannes Berg authored
commit cb150b9d upstream. Since cfg80211 frequently takes actions from its netdev notifier call, wireless extensions messages could still be ordered badly since the wext netdev notifier, since wext is built into the kernel, runs before the cfg80211 netdev notifier. For example, the following can happen: 5: wlan1: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN group default link/ether 02:00:00:00:01:00 brd ff:ff:ff:ff:ff:ff 5: wlan1: <BROADCAST,MULTICAST,UP> link/ether when setting the interface down causes the wext message. To also fix this, export the wireless_nlevent_flush() function and also call it from the cfg80211 notifier. Signed-off-by:
-
Johannes Berg authored
commit 8bf86273 upstream. Beniamino reported that he was getting an RTM_NEWLINK message for a given interface, after the RTM_DELLINK for it. It turns out that the message is a wireless extensions message, which was sent because the interface had been connected and disconnection while it was deleted caused a wext message. For its netlink messages, wext uses RTM_NEWLINK, but the message is without all the regular rtnetlink attributes, so "ip monitor link" prints just rudimentary information: 5: wlan1: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN group default link/ether 02:00:00:00:01:00 brd ff:ff:ff:ff:ff:ff Deleted 5: wlan1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default link/ether 02:00:00:00:01:00 brd ff:ff:ff:ff:ff:ff 5: wlan1: <BROADCAST,MULTICAST,UP> link/ether (from my hwsim reproduction) This can cause userspace to get confused since it doesn't expect an RTM_NEWLINK message after RTM_DELLINK. The reason for this is that wext schedules a worker to send out the messages, and the scheduling delay can cause the messages to get out to userspace in different order. To fix this, have wext register a netdevice notifier and flush out any pending messages when netdevice state changes. This fixes any ordering whenever the original message wasn't sent by a notifier itself. Reported-by:
Beniamino Galvani <bgalvani@redhat.com> Signed-off-by:
-
Konstantin Khlebnikov authored
commit b5891cfa upstream. This adds missing .d_select_inode into alternative dentry_operations. Signed-off-by:
Konstantin Khlebnikov <koct9i@gmail.com> Fixes: 7c03b5d4 ("ovl: allow distributed fs as lower layer") Fixes: 4bacc9c9 ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay") Reviewed-by:
Nikolay Borisov <kernel@kyup.com> Tested-by:
Miklos Szeredi <miklos@szeredi.hu> Signed-off-by:
-
Konstantin Khlebnikov authored
commit 45d11738 upstream. After rename file dentry still holds reference to lower dentry from previous location. This doesn't matter for data access because data comes from upper dentry. But this stale lower dentry taints dentry at new location and turns it into non-pure upper. Such file leaves visible whiteout entry after remove in directory which shouldn't have whiteouts at all. Overlayfs already tracks pureness of file location in oe->opaque. This patch just uses that for detecting actual path type. Comment from Vivek Goyal's patch: Here are the details of the problem. Do following. $ mkdir upper lower work merged upper/dir/ $ touch lower/test $ sudo mount -t overlay overlay -olowerdir=lower,upperdir=upper,workdir= work merged $ mv merged/test merged/dir/ $ rm merged/dir/test $ ls -l merged/dir/ /usr/bin/ls: cannot access merged/dir/test: No such file or directory total 0 c????????? ? ? ? ? ? test Basic problem seems to be that once a file has been unlinked, a whiteout has been left behind which was not needed and hence it becomes visible. Whiteout is visible because parent dir is of not type MERGE, hence od->is_real is set during ovl_dir_open(). And that means ovl_iterate() passes on iterate handling directly to underlying fs. Underlying fs does not know/filter whiteouts so it becomes visible to user. Why did we leave a whiteout to begin with when we should not have. ovl_do_remove() checks for OVL_TYPE_PURE_UPPER() and does not leave whiteout if file is pure upper. In this case file is not found to be pure upper hence whiteout is left. So why file was not PURE_UPPER in this case? I think because dentry is still carrying some leftover state which was valid before rename. For example, od->numlower was set to 1 as it was a lower file. After rename, this state is not valid anymore as there is no such file in lower. Signed-off-by:
Viktor Stanchev <me@viktorstanchev.com> Suggested-by:
Vivek Goyal <vgoyal@redhat.com> Link: https://bugzilla.kernel.org/show_bug.cgi?id=109611Acked-by:
-
Takashi Iwai authored
commit d0784829 upstream. "MBC Mode", "VSS Mode", "VSS HPF Mode" and "Enhanced EQ Mode" ctls in wm8958 codec driver are enum, while the current driver accesses wrongly via value.integer.value[]. They have to be via value.enumerated.item[] instead. Signed-off-by:
Takashi Iwai <tiwai@suse.de> Signed-off-by:
Mark Brown <broonie@kernel.org> Signed-off-by:
-
Takashi Iwai authored
commit 8019c0b3 upstream. The DRC Mode like "AIF1DRC1 Mode" and EQ Mode like "AIF1.1 EQ Mode" in wm8994 codec driver are enum ctls, while the current driver accesses wrongly via value.integer.value[]. They have to be via value.enumerated.item[] instead. Signed-off-by:
-
Charles Keepax authored
commit 316fa9e0 upstream. Lockdep warns of a potential lock inversion, i2s->lock is held numerous times whilst we are under the substream lock (snd_pcm_stream_lock). If we use the IRQ unsafe spin lock calls, you can also end up locking snd_pcm_stream_lock whilst under i2s->lock (if an IRQ happens whilst we are holding i2s->lock). This could result in deadlock. [ 18.147001] CPU0 CPU1 [ 18.151509] ---- ---- [ 18.156022] lock(&(&pri_dai->spinlock)->rlock); [ 18.160701] local_irq_disable(); [ 18.166622] lock(&(&substream->self_group.lock)->rlock); [ 18.174595] lock(&(&pri_dai->spinlock)->rlock); [ 18.181806] <Interrupt> [ 18.184408] lock(&(&substream->self_group.lock)->rlock); [ 18.190045] [ 18.190045] *** DEADLOCK *** This patch changes to using the irq safe spinlock calls, to avoid this issue. Fixes: ce8bcdbb ("ASoC: samsung: i2s: Protect more registers with a spinlock") Signed-off-by:
Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Tested-by:
Anand Moon <linux.amoon@gmail.com> Signed-off-by:
-
Takashi Iwai authored
commit 741338f9 upstream. snd_soc_dapm_dai_link_get() and _put() access the associated ctl values as value.integer.value[]. However, this is an enum ctl, and it has to be accessed via value.enumerated.item[]. The former is long while the latter is unsigned int, so they don't align. Fixes: c6615082 ('ASoC: dapm: add code to configure dai link parameters') Signed-off-by:
-
Al Viro authored
commit 803c0012 upstream. Failing to allocate an inode for child means that cache for *parent* is incompletely populated. So it's parent directory inode ('dir') that needs NCPI_DIR_CACHE flag removed, *not* the child inode ('inode', which is what we'd failed to allocate in the first place). Fucked-up-in: commit 5e993e25 ("ncpfs: get rid of d_validate() nonsense") Fucked-up-by:
Al Viro <viro@zeniv.linux.org.uk> Signed-off-by:
-
Al Viro authored
commit f9381284 upstream. d_instantiate(new_dentry, old_inode) is absolutely wrong thing to do - it will oops if new_dentry used to be positive, for starters. What we need is d_invalidate() the target and be done with that. Signed-off-by:
-
Ludovic Desroches authored
commit 25c5e962 upstream. When computing the residue we need two pieces of information: the current descriptor and the remaining data of the current descriptor. To get that information, we need to read consecutively two registers but we can't do it in an atomic way. For that reason, we have to check manually that current descriptor has not changed. Signed-off-by:
Ludovic Desroches <ludovic.desroches@atmel.com> Suggested-by:
Cyrille Pitchen <cyrille.pitchen@atmel.com> Reported-by:
David Engraf <david.engraf@sysgo.com> Tested-by:
Vinod Koul <vinod.koul@intel.com> Signed-off-by:
-
Steven Rostedt (Red Hat) authored
commit dc17147d upstream. Commit f3775549 ("tracepoints: Do not trace when cpu is offline") added a check to make sure that tracepoints only get called when the cpu is online, as it uses rcu_read_lock_sched() for protection. Commit 3a630178 ("tracing: generate RCU warnings even when tracepoints are disabled") added lockdep checks (including rcu checks) for events that are not enabled to catch possible RCU issues that would only be triggered if a trace event was enabled. Commit f3775549 only stopped the warnings when the trace event was enabled but did not prevent warnings if the trace event was called when disabled. To fix this, the cpu online check is moved to where the condition is added to the trace event. This will place the cpu online check in all places that it may be used now and in the future. Fixes: f3775549 ("tracepoints: Do not trace when cpu is offline") Fixes: 3a630178 ("tracing: generate RCU warnings even when tracepoints are disabled") Reported-by:
Sudeep Holla <sudeep.holla@arm.com> Tested-by:
Steven Rostedt <rostedt@goodmis.org> Signed-off-by:
-
Heiko Carstens authored
commit ce0c12b6 upstream. git commit 1ec2772e ("s390/diag: add a statistic for diagnose calls") added function calls to gather diagnose statistics. In case of the dasd diag driver the function call was added between a register asm statement which initialized register r2 and the inline assembly itself. The function call clobbers the contents of register r2 and therefore the diag 0x250 call behaves in a more or less random way. Fix this by extracting the function call into a separate function like we do everywhere else. Fixes: 1ec2772e ("s390/diag: add a statistic for diagnose calls") Reported-and-tested-by:
Stefan Haberland <sth@linux.vnet.ibm.com> Signed-off-by:
Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by:
Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by:
-
Martin Schwidefsky authored
commit 3446c13b upstream. The fork of a process with four page table levels is broken since git commit 6252d702 "[S390] dynamic page tables." All new mm contexts are created with three page table levels and an asce limit of 4TB. If the parent has four levels dup_mmap will add vmas to the new context which are outside of the asce limit. The subsequent call to copy_page_range will walk the three level page table structure of the new process with non-zero pgd and pud indexes. This leads to memory clobbers as the pgd_index *and* the pud_index is added to the mm->pgd pointer without a pgd_deref in between. The init_new_context() function is selecting the number of page table levels for a new context. The function is used by mm_init() which in turn is called by dup_mm() and mm_alloc(). These two are used by fork() and exec(). The init_new_context() function can distinguish the two cases by looking at mm->context.asce_limit, for fork() the mm struct has been copied and the number of page table levels may not change. For exec() the mm_alloc() function set the new mm structure to zero, in this case a three-level page table is created as the temporary stack space is located at STACK_TOP_MAX = 4TB. This fixes CVE-2016-2143. Reported-by:
Marcin Kościelnicki <koriakin@0x04.net> Reviewed-by:
-
Paolo Bonzini authored
commit 5f0b8199 upstream. KVM has special logic to handle pages with pte.u=1 and pte.w=0 when CR0.WP=1. These pages' SPTEs flip continuously between two states: U=1/W=0 (user and supervisor reads allowed, supervisor writes not allowed) and U=0/W=1 (supervisor reads and writes allowed, user writes not allowed). When SMEP is in effect, however, U=0 will enable kernel execution of this page. To avoid this, KVM also sets NX=1 in the shadow PTE together with U=0, making the two states U=1/W=0/NX=gpte.NX and U=0/W=1/NX=1. When guest EFER has the NX bit cleared, the reserved bit check thinks that the latter state is invalid; teach it that the smep_andnot_wp case will also use the NX bit of SPTEs. Reviewed-by:
Xiao Guangrong <guangrong.xiao@linux.inel.com> Fixes: c258b62bSigned-off-by:
Paolo Bonzini <pbonzini@redhat.com> Signed-off-by:
-
Paolo Bonzini authored
commit 844a5fe2 upstream. Yes, all of these are needed. :) This is admittedly a bit odd, but kvm-unit-tests access.flat tests this if you run it with "-cpu host" and of course ept=0. KVM runs the guest with CR0.WP=1, so it must handle supervisor writes specially when pte.u=1/pte.w=0/CR0.WP=0. Such writes cause a fault when U=1 and W=0 in the SPTE, but they must succeed because CR0.WP=0. When KVM gets the fault, it sets U=0 and W=1 in the shadow PTE and restarts execution. This will still cause a user write to fault, while supervisor writes will succeed. User reads will fault spuriously now, and KVM will then flip U and W again in the SPTE (U=1, W=0). User reads will be enabled and supervisor writes disabled, going back to the originary situation where supervisor writes fault spuriously. When SMEP is in effect, however, U=0 will enable kernel execution of this page. To avoid this, KVM also sets NX=1 in the shadow PTE together with U=0. If the guest has not enabled NX, the result is a continuous stream of page faults due to the NX bit being reserved. The fix is to force EFER.NX=1 even if the CPU is taking care of the EFER switch. (All machines with SMEP have the CPU_LOAD_IA32_EFER vm-entry control, so they do not use user-return notifiers for EFER---if they did, EFER.NX would be forced to the same value as the host). There is another bug in the reserved bit check, which I've split to a separate patch for easier application to stable kernels. Cc: Andy Lutomirski <luto@amacapital.net> Reviewed-by:
Xiao Guangrong <guangrong.xiao@linux.intel.com> Fixes: f6577a5fSigned-off-by:
-
Paul Mackerras authored
commit ccec4456 upstream. Thomas Huth discovered that a guest could cause a hard hang of a host CPU by setting the Instruction Authority Mask Register (IAMR) to a suitable value. It turns out that this is because when the code was added to context-switch the new special-purpose registers (SPRs) that were added in POWER8, we forgot to add code to ensure that they were restored to a sane value on guest exit. This adds code to set those registers where a bad value could compromise the execution of the host kernel to a suitable neutral value on guest exit. Fixes: b005255eReported-by:
Thomas Huth <thuth@redhat.com> Reviewed-by:
David Gibson <david@gibson.dropbear.id.au> Signed-off-by:
Paul Mackerras <paulus@samba.org> Signed-off-by:
-
David Hildenbrand authored
commit 9522b37f upstream. With MACHINE_HAS_VX, we convert the floating point registers from the vector registeres when storing the status. For other VCPUs, these are stored to vcpu->run->s.regs.vrs, but we are using current->thread.fpu.vxrs, which resolves to the currently loaded VCPU. So kvm_s390_store_status_unloaded() currently writes the wrong floating point registers (converted from the vector registers) when called from another VCPU on a z13. This is only the case for old user space not handling SIGP STORE STATUS and SIGP STOP AND STORE STATUS, but relying on the kernel implementation. All other calls come from the loaded VCPU via kvm_s390_store_status(). Fixes: 9abc2a08 (KVM: s390: fix memory overwrites when vx is disabled) Reviewed-by:
Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by:
David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by:
-
Radim Krčmář authored
commit 7099e2e1 upstream. Linux guests on Haswell (and also SandyBridge and Broadwell, at least) would crash if you decided to run a host command that uses PEBS, like perf record -e 'cpu/mem-stores/pp' -a This happens because KVM is using VMX MSR switching to disable PEBS, but SDM [2015-12] 18.4.4.4 Re-configuring PEBS Facilities explains why it isn't safe: When software needs to reconfigure PEBS facilities, it should allow a quiescent period between stopping the prior event counting and setting up a new PEBS event. The quiescent period is to allow any latent residual PEBS records to complete its capture at their previously specified buffer address (provided by IA32_DS_AREA). There might not be a quiescent period after the MSR switch, so a CPU ends up using host's MSR_IA32_DS_AREA to access an area in guest's memory. (Or MSR switching is just buggy on some models.) The guest can learn something about the host this way: If the guest doesn't map address pointed by MSR_IA32_DS_AREA, it results in #PF where we leak host's MSR_IA32_DS_AREA through CR2. After that, a malicious guest can map and configure memory where MSR_IA32_DS_AREA is pointing and can therefore get an output from host's tracing. This is not a critical leak as the host must initiate with PEBS tracing and I have not been able to get a record from more than one instruction before vmentry in vmx_vcpu_run() (that place has most registers already overwritten with guest's). We could disable PEBS just few instructions before vmentry, but disabling it earlier shouldn't affect host tracing too much. We also don't need to switch MSR_IA32_PEBS_ENABLE on VMENTRY, but that optimization isn't worth its code, IMO. (If you are implementing PEBS for guests, be sure to handle the case where both host and guest enable PEBS, because this patch doesn't.) Fixes: 26a4f3c0 ("perf/x86: disable PEBS on a guest entry.") Reported-by:
Jiří Olša <jolsa@redhat.com> Signed-off-by:
Radim Krčmář <rkrcmar@redhat.com> Signed-off-by:
-
David Matlack authored
commit 313f636d upstream. When growing halt-polling, there is no check that the poll time exceeds the limit. It's possible for vcpu->halt_poll_ns grow once past halt_poll_ns, and stay there until a halt which takes longer than vcpu->halt_poll_ns. For example, booting a Linux guest with halt_poll_ns=11000: ... kvm:kvm_halt_poll_ns: vcpu 0: halt_poll_ns 0 (shrink 10000) ... kvm:kvm_halt_poll_ns: vcpu 0: halt_poll_ns 10000 (grow 0) ... kvm:kvm_halt_poll_ns: vcpu 0: halt_poll_ns 20000 (grow 10000) Signed-off-by:
David Matlack <dmatlack@google.com> Fixes: aca6ff29Signed-off-by:
-
Krzysztof Hałasa authored
commit 54c6e2dd upstream. pci_create_root_bus() passes a "parent" pointer to pci_bus_assign_domain_nr(). When CONFIG_PCI_DOMAINS_GENERIC is defined, pci_bus_assign_domain_nr() dereferences that pointer. Many callers of pci_create_root_bus() supply a NULL "parent" pointer, which leads to a NULL pointer dereference error. 7c674700 ("PCI: Move domain assignment from arm64 to generic code") moved the "parent" dereference from arm64 to generic code. Only arm64 used that code (because only arm64 defined CONFIG_PCI_DOMAINS_GENERIC), and it always supplied a valid "parent" pointer. Other arches supplied NULL "parent" pointers but didn't defined CONFIG_PCI_DOMAINS_GENERIC, so they used a no-op version of pci_bus_assign_domain_nr(). 8c7d1474 ("ARM/PCI: Move to generic PCI domains") defined CONFIG_PCI_DOMAINS_GENERIC on ARM, and many ARM platforms use pci_common_init(), which supplies a NULL "parent" pointer. These platforms (cns3xxx, dove, footbridge, iop13xx, etc.) crash with a NULL pointer dereference like this while probing PCI: Unable to handle kernel NULL pointer dereference at virtual address 000000a4 PC is at pci_bus_assign_domain_nr+0x10/0x84 LR is at pci_create_root_bus+0x48/0x2e4 Kernel panic - not syncing: Attempted to kill init! [bhelgaas: changelog, add "Reported:" and "Fixes:" tags] Reported: http://forum.doozan.com/read.php?2,17868,22070,quote=1 Fixes: 8c7d1474 ("ARM/PCI: Move to generic PCI domains") Fixes: 7c674700 ("PCI: Move domain assignment from arm64 to generic code") Signed-off-by:
Krzysztof Hałasa <khalasa@piap.pl> Signed-off-by:
Bjorn Helgaas <bhelgaas@google.com> Acked-by:
Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by:
-
Lokesh Vutla authored
commit 2e18f5a1 upstream. Introduce a dt property, ti,no-idle, that prevents an IP to idle at any point. This is to handle Errata i877, which tells that GMAC clocks cannot be disabled. Acked-by:
Roger Quadros <rogerq@ti.com> Tested-by:
Mugunthan V N <mugunthanvnm@ti.com> Signed-off-by:
Lokesh Vutla <lokeshvutla@ti.com> Signed-off-by:
Sekhar Nori <nsekhar@ti.com> Signed-off-by:
Dave Gerlach <d-gerlach@ti.com> Acked-by:
Rob Herring <robh@kernel.org> Signed-off-by:
Paul Walmsley <paul@pwsan.com> Signed-off-by:
-
