- 22 Aug, 2016 40 commits
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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:
Lyude <cpaul@redhat.com> [danvet: Clarify why we need this.] Signed-off-by:
Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1463065021-18280-2-git-send-email-cpaul@redhat.com [bwh: Backported to 3.16: adjust context] Signed-off-by:
Ben Hutchings <ben@decadent.org.uk>
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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:
Herbert Xu <herbert@gondor.apana.org.au> Acked-by:
Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by:
David S. Miller <davem@davemloft.net> 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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Naveen N. Rao authored
commit f4782207 upstream. On some architectures (powerpc in particular), the number of registers exceeds what can be represented in an integer bitmask. Ensure we generate the proper bitmask on such platforms. Fixes: 71ad0f5e ("perf tools: Support for DWARF CFI unwinding on post processing") Signed-off-by:
Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by:
Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by:
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Michael Ellerman authored
commit aac55d75 upstream. With Linux page size of 64K and hardware only supporting 4K HPTE, if we use subpage protection, we always fail for the subpage 0 as shown below (using the selftest subpage_prot test): 520175565: (4520111850): Failed at 0x3fffad4b0000 (p=13,sp=0,w=0), want=fault, got=pass ! 4520890210: (4520826495): Failed at 0x3fffad5b0000 (p=29,sp=0,w=0), want=fault, got=pass ! 4521574251: (4521510536): Failed at 0x3fffad6b0000 (p=45,sp=0,w=0), want=fault, got=pass ! 4522258324: (4522194609): Failed at 0x3fffad7b0000 (p=61,sp=0,w=0), want=fault, got=pass ! This is because hash preload wrongly inserts the HPTE entry for subpage 0 without looking at the subpage protection information. Fix it by teaching should_hash_preload() not to preload if we have subpage protection configured for that range. It appears this has been broken since it was introduced in 2008. Fixes: fa28237c ("[POWERPC] Provide a way to protect 4k subpages when using 64k pages") Signed-off-by:
Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> [mpe: Rework into should_hash_preload() to avoid build fails w/SLICES=n] Signed-off-by:
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Michael Ellerman authored
commit 8bbc9b7b upstream. Currently we have a check in hash_preload() against the psize, which is only included when CONFIG_PPC_MM_SLICES is enabled. We want to expand this check in a subsequent patch, so factor it out to allow that. As a bonus it removes the #ifdef in the C code. Unfortunately we can't put this in the existing CONFIG_PPC_MM_SLICES block because it would require a forward declaration. Signed-off-by:
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Arnd Bergmann authored
commit c9c6837d upstream. gcc-6 started warning by default about variables that are not used anywhere and that are marked 'const', generating many false positives in an allmodconfig build, e.g.: arch/arm/mach-davinci/board-da830-evm.c:282:20: warning: 'da830_evm_emif25_pins' defined but not used [-Wunused-const-variable=] arch/arm/plat-omap/dmtimer.c:958:34: warning: 'omap_timer_match' defined but not used [-Wunused-const-variable=] drivers/bluetooth/hci_bcm.c:625:39: warning: 'acpi_bcm_default_gpios' defined but not used [-Wunused-const-variable=] drivers/char/hw_random/omap-rng.c:92:18: warning: 'reg_map_omap4' defined but not used [-Wunused-const-variable=] drivers/devfreq/exynos/exynos5_bus.c:381:32: warning: 'exynos5_busfreq_int_pm' defined but not used [-Wunused-const-variable=] drivers/dma/mv_xor.c:1139:34: warning: 'mv_xor_dt_ids' defined but not used [-Wunused-const-variable=] This is similar to the existing -Wunused-but-set-variable warning that was added in an earlier release and that we disable by default now and only enable when W=1 is set, so it makes sense to do the same here. Once we have eliminated the majority of the warnings for both, we can put them back into the default list. We probably want this in backport kernels as well, to allow building them with gcc-6 without introducing extra warnings. Signed-off-by:
Arnd Bergmann <arnd@arndb.de> Acked-by:
Olof Johansson <olof@lixom.net> Acked-by:
Lee Jones <lee.jones@linaro.org> Signed-off-by:
Michal Marek <mmarek@suse.com> Signed-off-by:
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Julien Grall authored
commit f228b494 upstream. The loop that browses the array compat_hwcap_str will stop when a NULL is encountered, however NULL is missing at the end of array. This will lead to overrun until a NULL is found somewhere in the following memory. In reality, this works out because the compat_hwcap2_str array tends to follow immediately in memory, and that *is* terminated correctly. Furthermore, the unsigned int compat_elf_hwcap is checked before printing each capability, so we end up doing the right thing because the size of the two arrays is less than 32. Still, this is an obvious mistake and should be fixed. Note for backporting: commit 12d11817 ("arm64: Move /proc/cpuinfo handling code") moved this code in v4.4. Prior to that commit, the same change should be made in arch/arm64/kernel/setup.c. Fixes: 44b82b77 "arm64: Fix up /proc/cpuinfo" Signed-off-by:
Julien Grall <julien.grall@arm.com> Signed-off-by:
Will Deacon <will.deacon@arm.com> [bwh: Backported to 3.16: adjust filename] Signed-off-by:
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Will Deacon authored
commit f86c4fbd upstream. When an IPI is generated by a CPU, the pattern looks roughly like: <write shared data> smp_wmb(); <write to GIC to signal SGI> On the receiving CPU we rely on the fact that, once we've taken the interrupt, then the freshly written shared data must be visible to us. Put another way, the CPU isn't going to speculate taking an interrupt. Unfortunately, this assumption turns out to be broken. Consider that CPUx wants to send an IPI to CPUy, which will cause CPUy to read some shared_data. Before CPUx has done anything, a random peripheral raises an IRQ to the GIC and the IRQ line on CPUy is raised. CPUy then takes the IRQ and starts executing the entry code, heading towards gic_handle_irq. Furthermore, let's assume that a bunch of the previous interrupts handled by CPUy were SGIs, so the branch predictor kicks in and speculates that irqnr will be <16 and we're likely to head into handle_IPI. The prefetcher then grabs a speculative copy of shared_data which contains a stale value. Meanwhile, CPUx gets round to updating shared_data and asking the GIC to send an SGI to CPUy. Internally, the GIC decides that the SGI is more important than the peripheral interrupt (which hasn't yet been ACKed) but doesn't need to do anything to CPUy, because the IRQ line is already raised. CPUy then reads the ACK register on the GIC, sees the SGI value which confirms the branch prediction and we end up with a stale shared_data value. This patch fixes the problem by adding an smp_rmb() to the IPI entry code in gic_handle_irq. As it turns out, the combination of a control dependency and an ISB instruction from the EOI in the GICv3 driver is enough to provide the ordering we need, so we add a comment there justifying the absence of an explicit smp_rmb(). Signed-off-by:
Marc Zyngier <marc.zyngier@arm.com> [bwh: Backported to 3.16: drop changes to irq-gic-v3] Signed-off-by:
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Heiko Carstens authored
commit c34a6905 upstream. The identity mapping is suboptimal for the last 2GB frame. The mapping will be established with a mix of 4KB and 1MB mappings instead of a single 2GB mapping. This happens because of a off-by-one bug introduced with commit 50be6345 ("s390/mm: Convert bootmem to memblock"). Currently the identity mapping looks like this: 0x0000000080000000-0x0000000180000000 4G PUD RW 0x0000000180000000-0x00000001fff00000 2047M PMD RW 0x00000001fff00000-0x0000000200000000 1M PTE RW With the bug fixed it looks like this: 0x0000000080000000-0x0000000200000000 6G PUD RW Fixes: 50be6345 ("s390/mm: Convert bootmem to memblock") Signed-off-by:
Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by:
Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by:
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Mans Rullgard authored
commit 55e610cd upstream. This lock is already taken in ata_scsi_queuecmd() a few levels up the call stack so attempting to take it here is an error. Moreover, it is pointless in the first place since it only protects a single, atomic assignment. Enabling lock debugging gives the following output: ============================================= [ INFO: possible recursive locking detected ] 4.4.0-rc5+ #189 Not tainted --------------------------------------------- kworker/u2:3/37 is trying to acquire lock: (&(&host->lock)->rlock){-.-...}, at: [<90283294>] sata_dwc_exec_command_by_tag.constprop.14+0x44/0x8c but task is already holding lock: (&(&host->lock)->rlock){-.-...}, at: [<902761ac>] ata_scsi_queuecmd+0x2c/0x330 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&(&host->lock)->rlock); lock(&(&host->lock)->rlock); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by kworker/u2:3/37: #0: ("events_unbound"){.+.+.+}, at: [<9003a0a4>] process_one_work+0x12c/0x430 #1: ((&entry->work)){+.+.+.}, at: [<9003a0a4>] process_one_work+0x12c/0x430 #2: (&bdev->bd_mutex){+.+.+.}, at: [<9011fd54>] __blkdev_get+0x50/0x380 #3: (&(&host->lock)->rlock){-.-...}, at: [<902761ac>] ata_scsi_queuecmd+0x2c/0x330 stack backtrace: CPU: 0 PID: 37 Comm: kworker/u2:3 Not tainted 4.4.0-rc5+ #189 Workqueue: events_unbound async_run_entry_fn Stack : 90b38e30 00000021 00000003 9b2a6040 00000000 9005f3f0 904fc8dc 00000025 906b96e4 00000000 90528648 9b3336c4 904fc8dc 9009bf18 00000002 00000004 00000000 00000000 9b3336c4 9b3336e4 904fc8dc 9003d074 00000000 90500000 9005e738 00000000 00000000 00000000 00000000 00000000 00000000 00000000 6e657665 755f7374 756f626e 0000646e 00000000 00000000 9b00ca00 9b025000 ... Call Trace: [<90009d6c>] show_stack+0x88/0xa4 [<90057744>] __lock_acquire+0x1ce8/0x2154 [<900583e4>] lock_acquire+0x64/0x8c [<9045ff10>] _raw_spin_lock_irqsave+0x54/0x78 [<90283294>] sata_dwc_exec_command_by_tag.constprop.14+0x44/0x8c [<90283484>] sata_dwc_qc_issue+0x1a8/0x24c [<9026b39c>] ata_qc_issue+0x1f0/0x410 [<90273c6c>] ata_scsi_translate+0xb4/0x200 [<90276234>] ata_scsi_queuecmd+0xb4/0x330 [<9025800c>] scsi_dispatch_cmd+0xd0/0x128 [<90259934>] scsi_request_fn+0x58c/0x638 [<901a3e50>] __blk_run_queue+0x40/0x5c [<901a83d4>] blk_queue_bio+0x27c/0x28c [<901a5914>] generic_make_request+0xf0/0x188 [<901a5a54>] submit_bio+0xa8/0x194 [<9011adcc>] submit_bh_wbc.isra.23+0x15c/0x17c [<9011c908>] block_read_full_page+0x3e4/0x428 [<9009e2e0>] do_read_cache_page+0xac/0x210 [<9009fd90>] read_cache_page+0x18/0x24 [<901bbd18>] read_dev_sector+0x38/0xb0 [<901bd174>] msdos_partition+0xb4/0x5c0 [<901bcb8c>] check_partition+0x140/0x274 [<901bba60>] rescan_partitions+0xa0/0x2b0 [<9011ff68>] __blkdev_get+0x264/0x380 [<901201ac>] blkdev_get+0x128/0x36c [<901b9378>] add_disk+0x3c0/0x4bc [<90268268>] sd_probe_async+0x100/0x224 [<90043a44>] async_run_entry_fn+0x50/0x124 [<9003a11c>] process_one_work+0x1a4/0x430 [<9003a4f4>] worker_thread+0x14c/0x4fc [<900408f4>] kthread+0xd0/0xe8 [<90004338>] ret_from_kernel_thread+0x14/0x1c Fixes: 62936009 ("[libata] Add 460EX on-chip SATA driver, sata_dwc_460ex") Tested-by:
Christian Lamparter <chunkeey@googlemail.com> Signed-off-by:
Mans Rullgard <mans@mansr.com> Signed-off-by:
Tejun Heo <tj@kernel.org> Signed-off-by:
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Arnd Bergmann authored
commit c87bf431 upstream. Enabling CONFIG_GCOV_PROFILE_ALL produces us a lot of warnings like lib/lz4/lz4hc_compress.c: In function 'lz4_compresshcctx': lib/lz4/lz4hc_compress.c:514:1: warning: the frame size of 1504 bytes is larger than 1024 bytes [-Wframe-larger-than=] After some investigation, I found that this behavior started with gcc-4.9, and opened https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69702. A suggested workaround for it is to use the -fno-tree-loop-im flag that turns off one of the optimization stages in gcc, so the code runs a little slower but does not use excessive amounts of stack. We could make this conditional on the gcc version, but I could not find an easy way to do this in Kbuild and the benefit would be fairly small, given that most of the gcc version in production are affected now. I'm marking this for 'stable' backports because it addresses a bug with code generation in gcc that exists in all kernel versions with the affected gcc releases. Signed-off-by:
Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by:
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James Hogan authored
commit b45bacd2 upstream. Writing CP0_Compare clears the timer interrupt pending bit (CP0_Cause.TI), but this wasn't being done atomically. If a timer interrupt raced with the write of the guest CP0_Compare, the timer interrupt could end up being pending even though the new CP0_Compare is nowhere near CP0_Count. We were already updating the hrtimer expiry with kvm_mips_update_hrtimer(), which used both kvm_mips_freeze_hrtimer() and kvm_mips_resume_hrtimer(). Close the race window by expanding out kvm_mips_update_hrtimer(), and clearing CP0_Cause.TI and setting CP0_Compare between the freeze and resume. Since the pending timer interrupt should not be cleared when CP0_Compare is written via the KVM user API, an ack argument is added to distinguish the source of the write. Fixes: e30492bb ("MIPS: KVM: Rewrite count/compare timer emulation") Signed-off-by:
James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim KrÄmáÅ
™ " <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Signed-off-by:Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 3.16: adjust filenames] Signed-off-by:
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James Hogan authored
commit 4355c44f upstream. There's a particularly narrow and subtle race condition when the software emulated guest timer is frozen which can allow a guest timer interrupt to be missed. This happens due to the hrtimer expiry being inexact, so very occasionally the freeze time will be after the moment when the emulated CP0_Count transitions to the same value as CP0_Compare (so an IRQ should be generated), but before the moment when the hrtimer is due to expire (so no IRQ is generated). The IRQ won't be generated when the timer is resumed either, since the resume CP0_Count will already match CP0_Compare. With VZ guests in particular this is far more likely to happen, since the soft timer may be frozen frequently in order to restore the timer state to the hardware guest timer. This happens after 5-10 hours of guest soak testing, resulting in an overflow in guest kernel timekeeping calculations, hanging the guest. A more focussed test case to intentionally hit the race (with the help of a new hypcall to cause the timer state to migrated between hardware & software) hits the condition fairly reliably within around 30 seconds. Instead of relying purely on the inexact hrtimer expiry to determine whether an IRQ should be generated, read the guest CP0_Compare and directly check whether the freeze time is before or after it. Only if CP0_Count is on or after CP0_Compare do we check the hrtimer expiry to determine whether the last IRQ has already been generated (which will have pushed back the expiry by one timer period). Fixes: e30492bb ("MIPS: KVM: Rewrite count/compare timer emulation") Signed-off-by:
™ " <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Signed-off-by: -
Johan Hovold authored
commit 028c49f5 upstream. The interface read URB is submitted in attach, but was only unlinked by the driver at disconnect. In case of a late probe error (e.g. due to failed minor allocation), disconnect is never called and we would end up with active URBs for an unbound interface. This in turn could lead to deallocated memory being dereferenced in the completion callback. Fixes: f7a33e60 ("USB: serial: add quatech2 usb to serial driver") Signed-off-by:
Johan Hovold <johan@kernel.org> Acked-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by:
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Johan Hovold authored
commit 9e452849 upstream. The interface read and event URBs are submitted in attach, but were never explicitly unlinked by the driver. Instead the URBs would have been killed by usb-serial core on disconnect. In case of a late probe error (e.g. due to failed minor allocation), disconnect is never called and we could end up with active URBs for an unbound interface. This in turn could lead to deallocated memory being dereferenced in the completion callbacks. Fixes: ee467a1f ("USB: serial: add Moxa UPORT 12XX/14XX/16XX driver") Signed-off-by:
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Johan Hovold authored
commit 35be1a71 upstream. The interface instat and indat URBs were submitted in attach, but never unlinked in release before deallocating the corresponding transfer buffers. In the case of a late probe error (e.g. due to failed minor allocation), disconnect would not have been called before release, causing the buffers to be freed while the URBs are still in use. We'd also end up with active URBs for an unbound interface. Fixes: f9c99bb8 ("USB: usb-serial: replace shutdown with disconnect, release") Signed-off-by:
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Johan Hovold authored
commit c8d62957 upstream. URBs and buffers allocated in attach for Epic devices would never be deallocated in case of a later probe error (e.g. failure to allocate minor numbers) as disconnect is then never called. Fix by moving deallocation to release and making sure that the URBs are first unlinked. Fixes: f9c99bb8 ("USB: usb-serial: replace shutdown with disconnect, release") Signed-off-by:
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Johan Hovold authored
commit c5c0c555 upstream. Private data, URBs and buffers allocated for Epic devices during attach were never released on errors (e.g. missing endpoints). Fixes: 6e8cf775 ("USB: add EPIC support to the io_edgeport driver") Signed-off-by:
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Joshua Kinard authored
commit 12863939 upstream. Update the recent changes to set_pte() that were added in 46011e6e to handle R10000_LLSC_WAR, and format the assembly to match other areas of the MIPS tree using the same WAR. This also incorporates a patch recently sent in my Markos Chandras, "Remove local LL/SC preprocessor variants", so that patch doesn't need to be applied if this one is accepted. Signed-off-by:
Joshua Kinard <kumba@gentoo.org> Fixes: 46011e6e ("MIPS: Make set_pte() SMP safe.) Cc: David Daney <david.daney@cavium.com> Cc: Linux/MIPS <linux-mips@linux-mips.org> Patchwork: https://patchwork.linux-mips.org/patch/11103/Signed-off-by:
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James Hogan authored
commit 81a76d71 upstream. When showing backtraces in response to traps, for example crashes and address errors (usually unaligned accesses) when they are set in debugfs to be reported, unwind_stack will be used if the PC was in the kernel text address range. However since EVA it is possible for user and kernel address ranges to overlap, and even without EVA userland can still trigger an address error by jumping to a KSeg0 address. Adjust the check to also ensure that it was running in kernel mode. I don't believe any harm can come of this problem, since unwind_stack() is sufficiently defensive, however it is only meant for unwinding kernel code, so to be correct it should use the raw backtracing instead. Signed-off-by:
Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/11701/Signed-off-by:
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James Hogan authored
commit a816b306 upstream. When unwinding through IRQs and exceptions, the unwinding only continues if the PC is a kernel text address, however since EVA it is possible for user and kernel address ranges to overlap, potentially allowing unwinding to continue to user mode if the user PC happens to be in the kernel text address range. Adjust the check to also ensure that the register state from before the exception is actually running in kernel mode, i.e. !user_mode(regs). I don't believe any harm can come of this problem, since the PC is only output, the stack pointer is checked to ensure it resides within the task's stack page before it is dereferenced in search of the return address, and the return address register is similarly only output (if the PC is in a leaf function or the beginning of a non-leaf function). However unwind_stack() is only meant for unwinding kernel code, so to be correct the unwind should stop there. Signed-off-by:
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Florian Fainelli authored
commit cbbda6e7 upstream. BMIPS5000 have a PrID value of 0x5A00 and BMIPS5200 have a PrID value of 0x5B00, which, masked with 0x5A00, returns 0x5A00. Update all conditionals on the PrID to cover both variants since we are going to need this to enable BMIPS5200 SMP. The existing check, masking with 0xFF00 would not cover BMIPS5200 at all. Fixes: 68e6a783 ("MIPS: BMIPS: Add PRId for BMIPS5200 (Whirlwind)") Fixes: 6465460c ("MIPS: BMIPS: change compile time checks to runtime checks") Signed-off-by:
Florian Fainelli <f.fainelli@gmail.com> Cc: john@phrozen.org Cc: cernekee@gmail.com Cc: jogo@openwrt.org Cc: jaedon.shin@gmail.com Cc: jfraser@broadcom.com Cc: pgynther@google.com Cc: dragan.stancevic@gmail.com Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12279/Signed-off-by:
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James Hogan authored
commit 5daebc47 upstream. Commit 85efde6f ("make exported headers use strict posix types") changed the asm-generic siginfo.h to use the __kernel_* types, and commit 3a471cbc ("remove __KERNEL_STRICT_NAMES") make the internal types accessible only to the kernel, but the MIPS implementation hasn't been updated to match. Switch to proper types now so that the exported asm/siginfo.h won't produce quite so many compiler errors when included alone by a user program. Signed-off-by:
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