- 10 Jun, 2016 40 commits
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Matt Gumbel authored
commit 32ecd320 upstream. 008GE0 Toshiba mmc in some Intel Baytrail tablets responds to MMC_SEND_EXT_CSD in 450-600ms. This patch will... () Increase the long read time quirk timeout from 300ms to 600ms. Original author of that quirk says 300ms was only a guess and that the number may need to be raised in the future. () Add this specific MMC to the quirk Signed-off-by:
Matt Gumbel <matthew.k.gumbel@intel.com> Signed-off-by:
Adrian Hunter <adrian.hunter@intel.com> Signed-off-by:
Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by:
Kamal Mostafa <kamal@canonical.com>
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Ville Syrjälä authored
commit 7045c368 upstream. When we read out the watermark state from the hardware we're supposed to transfer that into the active watermarks, but currently we fail to any part of the active watermarks that isn't explicitly written. Let's clear it all upfront. Looks like this has been like this since the beginning, when I added the readout. No idea why I didn't clear it up. Cc: Matt Roper <matthew.d.roper@intel.com> Fixes: 243e6a44 ("drm/i915: Init HSW watermark tracking in intel_modeset_setup_hw_state()") Signed-off-by:
Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by:
Matt Roper <matthew.d.roper@intel.com> Signed-off-by:
Jani Nikula <jani.nikula@intel.com> Signed-off-by:
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Peter Zijlstra authored
commit 54cf809b upstream. Similar to commits: 51d7d520 ("powerpc: Add smp_mb() to arch_spin_is_locked()") d86b8da0 ("arm64: spinlock: serialise spin_unlock_wait against concurrent lockers") qspinlock suffers from the fact that the _Q_LOCKED_VAL store is unordered inside the ACQUIRE of the lock. And while this is not a problem for the regular mutual exclusive critical section usage of spinlocks, it breaks creative locking like: spin_lock(A) spin_lock(B) spin_unlock_wait(B) if (!spin_is_locked(A)) do_something() do_something() In that both CPUs can end up running do_something at the same time, because our _Q_LOCKED_VAL store can drop past the spin_unlock_wait() spin_is_locked() loads (even on x86!!). To avoid making the normal case slower, add smp_mb()s to the less used spin_unlock_wait() / spin_is_locked() side of things to avoid this problem. Reported-and-tested-by:
Davidlohr Bueso <dave@stgolabs.net> Reported-by:
Giovanni Gherdovich <ggherdovich@suse.com> Signed-off-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
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Stefan Bader authored
commit 4b50bcc7 upstream. Since commit 92923ca3 ("mm: meminit: only set page reserved in the memblock region") the reserved bit is set on reserved memblock regions. However start and end address are passed as unsigned long. This is only 32bit on i386, so it can end up marking the wrong pages reserved for ranges at 4GB and above. This was observed on a 32bit Xen dom0 which was booted with initial memory set to a value below 4G but allowing to balloon in memory (dom0_mem=1024M for example). This would define a reserved bootmem region for the additional memory (for example on a 8GB system there was a reverved region covering the 4GB-8GB range). But since the addresses were passed on as unsigned long, this was actually marking all pages from 0 to 4GB as reserved. Fixes: 92923ca3 ("mm: meminit: only set page reserved in the memblock region") Link: http://lkml.kernel.org/r/1463491221-10573-1-git-send-email-stefan.bader@canonical.comSigned-off-by:
Stefan Bader <stefan.bader@canonical.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> 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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Matt Evans authored
commit e4fe9e7d upstream. The EC field of the constructed ESR is conditionally modified by ORing in ESR_ELx_EC_DABT_LOW for a data abort. However, ESR_ELx_EC_SHIFT is missing from this condition. Signed-off-by:
Matt Evans <matt.evans@arm.com> Acked-by:
Marc Zyngier <marc.zyngier@arm.com> Signed-off-by:
Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by:
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Kai-Heng Feng authored
commit 423cd785 upstream. The headphone has noise when playing sound or switching microphone sources. It uses the same codec on XPS 13 9350, but with different subsystem ID. Applying the fixup can solve the issue. Also, changing the model name to better differentiate models. v2: Reorder by device ID. Signed-off-by:
Kai-Heng Feng <kai.heng.feng@canonical.com> Signed-off-by:
Takashi Iwai <tiwai@suse.de> 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> [ kamal: backport to 4.2-stable: keyring_alloc takes no restrict_link param ] Signed-off-by:
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Mark Brown authored
commit d3030d11 upstream. The ak4642 driver is using a regmap cache sync to restore the configuration of the chip on resume but (as Peter observed) does not actually define a register cache which means that the resume is never going to work and we trigger asserts in regmap. Fix this by enabling caching. Reported-by:
Geert Uytterhoeven <geert@linux-m68k.org> Reported-by:
Peter Ujfalusi <peter.ujfalusi@ti.com> Tested-by:
Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by:
Mark Brown <broonie@kernel.org> [ kamal: backport to 4.2-stable: no separate ak4643_regmap ] Signed-off-by:
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Andy Honig authored
commit 9842df62 upstream. MSR 0x2f8 accessed the 124th Variable Range MTRR ever since MTRR support was introduced by 9ba075a6 ("KVM: MTRR support"). 0x2f8 became harmful when 910a6aae ("KVM: MTRR: exactly define the size of variable MTRRs") shrinked the array of VR MTRRs from 256 to 8, which made access to index 124 out of bounds. The surrounding code only WARNs in this situation, thus the guest gained a limited read/write access to struct kvm_arch_vcpu. 0x2f8 is not a valid VR MTRR MSR, because KVM has/advertises only 16 VR MTRR MSRs, 0x200-0x20f. Every VR MTRR is set up using two MSRs, 0x2f8 was treated as a PHYSBASE and 0x2f9 would be its PHYSMASK, but 0x2f9 was not implemented in KVM, therefore 0x2f8 could never do anything useful and getting rid of it is safe. This fixes CVE-2016-3713. Fixes: 910a6aae ("KVM: MTRR: exactly define the size of variable MTRRs") Reported-by:
David Matlack <dmatlack@google.com> Signed-off-by:
Andy Honig <ahonig@google.com> Signed-off-by:
Radim Krčmář <rkrcmar@redhat.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com> 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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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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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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Maciej W. Rozycki authored
commit e49d3848 upstream. Fix a build regression from commit c9017757 ("MIPS: init upper 64b of vector registers when MSA is first used"): arch/mips/built-in.o: In function `enable_restore_fp_context': traps.c:(.text+0xbb90): undefined reference to `_init_msa_upper' traps.c:(.text+0xbb90): relocation truncated to fit: R_MIPS_26 against `_init_msa_upper' traps.c:(.text+0xbef0): undefined reference to `_init_msa_upper' traps.c:(.text+0xbef0): relocation truncated to fit: R_MIPS_26 against `_init_msa_upper' to !CONFIG_CPU_HAS_MSA configurations with older GCC versions, which are unable to figure out that calls to `_init_msa_upper' are indeed dead. Of the many ways to tackle this failure choose the approach we have already taken in `thread_msa_context_live'. [ralf@linux-mips.org: Drop patch segment to junk file.] Signed-off-by:
Maciej W. Rozycki <macro@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13271/Signed-off-by:
Ralf Baechle <ralf@linux-mips.org> 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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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:
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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 6b832257 upstream. Commit 9791554b ("MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPS") added support for the PR_SET_FP_MODE prctl, which allows a userland program to modify its FP mode at runtime. This is most notably required if dynamic linking leads to the FP mode requirement changing at runtime from that indicated in the initial executable's ELF header. In order to avoid overhead in the general FP context restore code, it aimed to have threads in the process become unable to enable the FPU during a mode switch & have the thread calling the prctl syscall wait for all other threads in the process to be context switched at least once. Once that happens we can know that no thread in the process whose mode will be switched has live FP context, and it's safe to perform the mode switch. However in the (rare) case of modeswitches occurring in multithreaded programs this can lead to indeterminate delays for the thread invoking the prctl syscall, and the code monitoring for those context switches was woefully inadequate for all but the simplest cases. Fix this by broadcasting an IPI if other CPUs may have live FP context for an affected thread, with a handler causing those CPUs to relinquish their FPU ownership. Threads will then be allowed to continue running but will stall on the wait_on_atomic_t in enable_restore_fp_context if they attempt to use FP again whilst the mode switch is still in progress. The end result is less fragile poking at scheduler context switch counts & a more expedient completion of the mode switch. Signed-off-by:
Paul Burton <paul.burton@imgtec.com> Fixes: 9791554b ("MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPS") Reviewed-by:
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Paul Burton authored
commit bd239f1e upstream. Whilst a PR_SET_FP_MODE prctl is performed there are decisions made based upon whether the task is executing on the current CPU. This may change if we're preempted, so disable preemption to avoid such changes for the lifetime of the mode switch. Signed-off-by:
Aurelien Jarno <aurelien@aurel32.net> Cc: Adam Buchbinder <adam.buchbinder@gmail.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/13144/Signed-off-by:
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Maciej W. Rozycki authored
commit abf378be upstream. Correct the cases missed with commit 9b26616c ("MIPS: Respect the ISA level in FCSR handling") and prevent writes to read-only FCSR bits there. This in particular applies to FP context initialisation where any IEEE 754-2008 bits preset by `mips_set_personality_nan' are cleared before the relevant ptrace(2) call takes effect and the PTRACE_POKEUSR request addressing FPC_CSR where no masking of read-only FCSR bits is done. Remove the FCSR clearing from FP context initialisation then and unify PTRACE_POKEUSR/FPC_CSR and PTRACE_SETFPREGS handling, by factoring out code from `ptrace_setfpregs' and calling it from both places. This mostly matters to soft float configurations where the emulator can be switched this way to a mode which should not be accessible and cannot be set with the CTC1 instruction. With hard float configurations any effect is transient anyway as read-only bits will retain their values at the time the FP context is restored. Signed-off-by:
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Maciej W. Rozycki authored
commit 42495484 upstream. Fix a floating-point context restoration regression introduced with commit 9b26616c ("MIPS: Respect the ISA level in FCSR handling") that causes a Floating Point exception and consequently a kernel oops with hard float configurations when one or more FCSR Enable and their corresponding Cause bits are set both at a time via a ptrace(2) call. To do so reinstate Cause bit masking originally introduced with commit b1442d39 ("MIPS: Prevent user from setting FCSR cause bits") to address this exact problem and then inadvertently removed from the PTRACE_SETFPREGS request with the commit referred above. 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:
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James Hogan authored
commit 987e5b83 upstream. Since commit 8cb48fe1 ("MIPS: Provide correct siginfo_t.si_stime"), MIPS' uapi/asm/siginfo.h has included uapi/asm-generic/siginfo.h directly before defining MIPS' struct siginfo, in order to get the necessary definitions needed for the siginfo struct without the generic copy_siginfo() hitting compiler errors due to struct siginfo not yet being defined. Now that the generic copy_siginfo() is moved out to linux/signal.h we can safely include asm-generic/siginfo.h before defining the MIPS specific struct siginfo, which avoids the uapi/ include as well as breakage due to generic copy_siginfo() being defined before struct siginfo. Reported-by:
Christopher Ferris <cferris@google.com> Fixes: 8cb48fe1 ("MIPS: Provide correct siginfo_t.si_stime") Signed-off-by:
James Hogan <james.hogan@imgtec.com> Cc: Petr Malat <oss@malat.biz> Cc: linux-mips@linux-mips.org Signed-off-by:
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James Hogan authored
commit ca9eb49a upstream. The generic copy_siginfo() is currently defined in asm-generic/siginfo.h, after including uapi/asm-generic/siginfo.h which defines the generic struct siginfo. However this makes it awkward for an architecture to use it if it has to define its own struct siginfo (e.g. MIPS and potentially IA64), since it means that asm-generic/siginfo.h can only be included after defining the arch-specific siginfo, which may be problematic if the arch-specific definition needs definitions from uapi/asm-generic/siginfo.h. It is possible to work around this by first including uapi/asm-generic/siginfo.h to get the constants before defining the arch-specific siginfo, and include asm-generic/siginfo.h after. However uapi headers can't be included by other uapi headers, so that first include has to be in an ifdef __kernel__, with the non __kernel__ case including the non-UAPI header instead. Instead of that mess, move the generic copy_siginfo() definition into linux/signal.h, which allows an arch-specific uapi/asm/siginfo.h to include asm-generic/siginfo.h and define the arch-specific siginfo, and for the generic copy_siginfo() to see that arch-specific definition. Signed-off-by:
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Paul Burton authored
commit 37d22a0d upstream. It's possible for pages to become visible prior to update_mmu_cache running if a thread within the same address space preempts the current thread or runs simultaneously on another CPU. That is, the following scenario is possible: CPU0 CPU1 write to page flush_dcache_page flush_icache_page set_pte_at map page update_mmu_cache If CPU1 maps the page in between CPU0's set_pte_at, which marks it valid & visible, and update_mmu_cache where the dcache flush occurs then CPU1s icache will fill from stale data (unless it fills from the dcache, in which case all is good, but most MIPS CPUs don't have this property). Commit 4d46a67a ("MIPS: Fix race condition in lazy cache flushing.") attempted to fix that by performing the dcache flush in flush_icache_page such that it occurs before the set_pte_at call makes the page visible. However it has the problem that not all code that writes to pages exposed to userland call flush_icache_page. There are many callers of set_pte_at under mm/ and only 2 of them do call flush_icache_page. Thus the race window between a page becoming visible & being coherent between the icache & dcache remains open in some cases. To illustrate some of the cases, a WARN was added to __update_cache with this patch applied that triggered in cases where a page about to be flushed from the dcache was not the last page provided to flush_icache_page. That is, backtraces were obtained for cases in which the race window is left open without this patch. The 2 standout examples follow. When forking a process: [ 15.271842] [<80417630>] __update_cache+0xcc/0x188 [ 15.277274] [<80530394>] copy_page_range+0x56c/0x6ac [ 15.282861] [<8042936c>] copy_process.part.54+0xd40/0x17ac [ 15.289028] [<80429f80>] do_fork+0xe4/0x420 [ 15.293747] [<80413808>] handle_sys+0x128/0x14c When exec'ing an ELF binary: [ 14.445964] [<80417630>] __update_cache+0xcc/0x188 [ 14.451369] [<80538d88>] move_page_tables+0x414/0x498 [ 14.457075] [<8055d848>] setup_arg_pages+0x220/0x318 [ 14.462685] [<805b0f38>] load_elf_binary+0x530/0x12a0 [ 14.468374] [<8055ec3c>] search_binary_handler+0xbc/0x214 [ 14.474444] [<8055f6c0>] do_execveat_common+0x43c/0x67c [ 14.480324] [<8055f938>] do_execve+0x38/0x44 [ 14.485137] [<80413808>] handle_sys+0x128/0x14c These code paths write into a page, call flush_dcache_page then call set_pte_at without flush_icache_page inbetween. The end result is that the icache can become corrupted & userland processes may execute unexpected or invalid code, typically resulting in a reserved instruction exception, a trap or a segfault. Fix this race condition fully by performing any cache maintenance required to keep the icache & dcache in sync in set_pte_at, before the page is made valid. This has the added bonus of ensuring the cache maintenance always happens in one location, rather than being duplicated in flush_icache_page & update_mmu_cache. It also matches the way other architectures solve the same problem (see arm, ia64 & powerpc). Signed-off-by:
Ionela Voinescu <ionela.voinescu@imgtec.com> Cc: Lars Persson <lars.persson@axis.com> Fixes: 4d46a67a ("MIPS: Fix race condition in lazy cache flushing.") Cc: Steven J. Hill <sjhill@realitydiluted.com> Cc: David Daney <david.daney@cavium.com> Cc: Huacai Chen <chenhc@lemote.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/12722/Signed-off-by:
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Paul Burton authored
commit f4281bba upstream. The following patch will expose __update_cache to highmem pages. Handle them by mapping them in for the duration of the cache maintenance, just like in __flush_dcache_page. The code for that isn't shared because we need the page address in __update_cache so sharing became messy. Given that the entirity is an extra 5 lines, just duplicate it. Signed-off-by:
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Guilherme G. Piccoli authored
commit c2078d9e upstream. This reverts commit 89a51df5. The function eeh_add_device_early() is used to perform EEH initialization in devices added later on the system, like in hotplug/DLPAR scenarios. Since the commit 89a51df5 ("powerpc/eeh: Fix crash in eeh_add_device_early() on Cell") a new check was introduced in this function - Cell has no EEH capabilities which led to kernel oops if hotplug was performed, so checking for eeh_enabled() was introduced to avoid the issue. However, in architectures that EEH is present like pSeries or PowerNV, we might reach a case in which no PCI devices are present on boot time and so EEH is not initialized. Then, if a device is added via DLPAR for example, eeh_add_device_early() fails because eeh_enabled() is false, and EEH end up not being enabled at all. This reverts the aforementioned patch since a new verification was introduced by the commit d91dafc0 ("powerpc/eeh: Delay probing EEH device during hotplug") and so the original Cell issue does not happen anymore. 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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Gavin Shan authored
commit 5a0cdbfd upstream. The function eeh_pe_reset_and_recover() is used to recover EEH error when the passthrou device are transferred to guest and backwards. The content in the device's config space will be lost on PE reset issued in the middle of the recovery. The function saves/restores it before/after the reset. However, config access to some adapters like Broadcom BCM5719 at this point will causes fenced PHB. The config space is always blocked and we save 0xFF's that are restored at late point. The memory BARs are totally corrupted, causing another EEH error upon access to one of the memory BARs. This restores the config space on those adapters like BCM5719 from the content saved to the EEH device when it's populated, to resolve above issue. Fixes: 5cfb20b9 ("powerpc/eeh: Emulate EEH recovery for VFIO devices") Signed-off-by:
Russell Currey <ruscur@russell.cc> Signed-off-by:
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Gavin Shan authored
commit affeb0f2 upstream. The function eeh_pe_reset_and_recover() is used to recover EEH error when the passthrough device are transferred to guest and backwards, meaning the device's driver is vfio-pci or none. When the driver is vfio-pci that provides error_detected() error handler only, the handler simply stops the guest and it's not expected behaviour. On the other hand, no error handlers will be called if we don't have a bound driver. This ignores the error handler in eeh_pe_reset_and_recover() that reports the error to device driver to avoid the exceptional behaviour. Fixes: 5cfb20b9 ("powerpc/eeh: Emulate EEH recovery for VFIO devices") 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:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
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