- 17 Aug, 2015 19 commits
-
-
Heiko Stuebner authored
The dw_mci_init_dma() may decide to not use dma, but pio instead, caused by things like wrong dma settings in the system. Till now the code dw_mci_init_slot() always assumed that dma is available when CONFIG_MMC_DW_IDMAC was defined, ignoring the host->use_dma var set during dma init. So when now the dma init failed for whatever reason, the transfer sizes would still be set for dma transfers, especially including the maximum block-count calculated from host->ring_size and resulting in a [ 4.991109] ------------[ cut here ]------------ [ 4.991111] kernel BUG at drivers/mmc/core/core.c:256! [ 4.991113] Internal error: Oops - BUG: 0 [#1] SMP ARM because host->ring_size is 0 in this case and the slot init code uses the wrong code to calculate the values. Fix this by selecting the correct calculations using the host->use_dma variable instead of the CONFIG_MMC_DW_IDMAC config option. Signed-off-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
-
Shawn Lin authored
This patch fixes the following issues reported by checkpatch.pl: - use -EINVAL instead of -ENOSYS, to fix warning message: "ENOSYS means 'invalid syscall nr' and nothing else" - split lines whose length is greater than 80 characters - avoid quoted string split across lines - use min_t instead of min, to fix warning message: "min() should probably be min_t(int, cnt, host->part_buf_count)" - fix missing a blank line after declarations Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
-
Alexey Brodkin authored
As per DW MobileStorage databook "each descriptor can transfer up to 4kB of data in chained mode", moreover buffer size that is put in "des1" is limited to 13 bits, i.e. for example on attempt to IDMAC_SET_BUFFER1_SIZE(desc, 8192) size value that's effectively written will be 0. On the platform with 8kB PAGE_SIZE I see dw_mmc gets data blocks in SG-list of 8kB size and that leads to unpredictable behavior of the SD/MMC controller. In particular on write to FAT partition of SD-card the controller will stuck in the middle of DMA transaction. Solution to the problem is simple - we need to pass large (> 4kB) data buffers to the controller via multiple descriptors. And that's what that change does. What's interesting I did try original driver on same platform but configured with 4kB PAGE_SIZE and may confirm that data blocks passed in SG-list to dw_mmc never exeed 4kB limit - that explains why nobody ever faced a problem I did. Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Cc: Seungwon Jeon <tgih.jun@samsung.com> Cc: Jaehoon Chung <jh80.chung@samsung.com> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: arc-linux-dev@synopsys.com Cc: linux-kernel@vger.kernel.org Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
-
Yangbo Lu authored
Some Sandisk cards(such as "SDMB-32" and "SDM032" cards) can't support CMD23, and would generate CMD timeout. So add FIX-UP for these two types Sandisk cards. Error log: mmcblk0: timed out sending SET_BLOCK_COUNT command, card status 0x400900 mmcblk0: timed out sending SET_BLOCK_COUNT command, card status 0x400900 mmcblk0: timed out sending SET_BLOCK_COUNT command, card status 0x400900 end_request: I/O error, dev mmcblk0, sector 0 Buffer I/O error on device mmcblk0, logical block 0 mmcblk0: timed out sending SET_BLOCK_COUNT command, card status 0x400900 Signed-off-by: Yangbo Lu <yangbo.lu@freescale.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
Yangbo Lu authored
eSDHC supports high speed mode, but has no enabling bit for it. Add this quirk to avoid writing to eSDHC_PROCTL[DTW] by mistake. Signed-off-by: Yangbo Lu <yangbo.lu@freescale.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
Yangbo Lu authored
For Freescale QorIQ LS1021AQDS board, there is a SDIO interrupt in the process of resume without inserting SD adapter because of some unknown issue. But the driver doesn't assign sdio_irq_thread pointer. This will block the resume of kernel. This patch is used to avoid using NULL sdio_irq_thread pointer. Signed-off-by: Yangbo Lu <yangbo.lu@freescale.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
Andreas Fenkart authored
Signed-off-by: Andreas Fenkart <afenkart@gmail.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
Andreas Fenkart authored
If no pdata.set_power was set by the platform code, the driver was updating pdata with its own fallback function. This is a no-no since pdata shall be read-only. This patch pushes the check 'pdata->set_power != NULL' down into the fallback functions. If pdata.set_power is really set, it calls them and exits, otherwise the fallback code is used. Signed-off-by: Andreas Fenkart <afenkart@gmail.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
Andreas Fenkart authored
Before 5b83b223 the driver was hard coding the wakeup irq to be active low. The generic pm wakeirq does not override the active high/low parameter, hence it must be specified correctly in the device tree. Mind that SDIO IRQ is active low as defined in the SDIO specification Signed-off-by: Andreas Fenkart <afenkart@gmail.com> Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
Ivan T. Ivanov authored
Controller could have both NO_CARD_NO_RESET and BROKEN_CARD_DETECTION quirks set. Use sdhci_do_get_cd() when applying NO_CARD_NO_RESET, which properly check for BROKEN_CARD_DETECTION quirk. Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
Ivan T. Ivanov authored
There is no reason to use polling for card detection state change when drivers are using dedicated GPIO for this. Don't poll in this case. Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
Ivan T. Ivanov authored
Controller could have BROKEN_CARD_DETECTION quirk set, but drivers could use GPIO to detect card present state. Let, when defined, GPIO take precedence, so drivers could properly detect card state and not use polling. Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
Ivan T. Ivanov authored
Ensure SDCC is working with maximum clock otherwise card detection could be extremely slow, up to 7 seconds. Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org> Reviewed-by: Georgi Djakov <georgi.djakov@linaro.org> Acked-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
Andy Shevchenko authored
It's excessive to use prefix for the parameters when you do modprobe mmc-block mmcblk.perdev_minors=16 Make this available only for built-in case. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
Fabian Frederick authored
See Documentation/DMA-API.txt - Part Id Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
Suneel Garapati authored
adding SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,SDHCI_QUIRK2_PRESET_VALUE_BROKEN flags for arasan sdhc. Signed-off-by: Suneel Garapati <suneel.garapati@xilinx.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
Suneel Garapati authored
adds quirk for controllers whose clock divider zero is broken, sdhci_set_clock function will incorporate this modification. Signed-off-by: Suneel Garapati <suneel.garapati@xilinx.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
Daniel Mack authored
Switch over pxamci to dmaengine. This prepares the devicetree full support of pxamci. This was successfully tested on a PXA3xx board, as well as PXA27x. Signed-off-by: Daniel Mack <zonque@gmail.com> [adapted to pxa-dma] Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
David Jander authored
In the (not so unlikely) case that the mmc controller timeout budget is enough for exactly one erase-group, the simplification of allowing one sector has an enormous performance penalty. We optimize this special case by introducing a flag that prohibits erase-group boundary crossing, so that we can allow trimming more than one sector at a time. Signed-off-by: David Jander <david@protonic.nl> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-
- 16 Aug, 2015 8 commits
-
-
Linus Torvalds authored
-
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-socLinus Torvalds authored
Pull ARM SoC fixes from Olof Johansson: "A smallish batch of fixes, a little more than expected this late, but all fixes are contained to their platforms and seem reasonably low risk: - a somewhat large SMP fix for ux500 that still seemed warranted to include here - OMAP DT fixes for pbias regulator specification that broke due to some DT reshuffling - PCIe IRQ routing bugfix for i.MX - networking fixes for keystone - runtime PM for OMAP GPMC - a couple of error path bug fixes for exynos" * tag 'armsoc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: ARM: dts: keystone: Fix the mdio bindings by moving it to soc specific file ARM: dts: keystone: fix the clock node for mdio memory: omap-gpmc: Don't try to save uninitialized GPMC context ARM: imx6: correct i.MX6 PCIe interrupt routing ARM: ux500: add an SMP enablement type and move cpu nodes ARM: dts: dra7: Fix broken pbias device creation ARM: dts: OMAP5: Fix broken pbias device creation ARM: dts: OMAP4: Fix broken pbias device creation ARM: dts: omap243x: Fix broken pbias device creation ARM: EXYNOS: fix double of_node_put() on error path ARM: EXYNOS: Fix potentian kfree() of ro memory
-
git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds authored
Pull MIPS bugfix from Ralf Baechle: "Only a single MIPS fix - the math when invoking syscall_trace_enter was wrong" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: MIPS: Fix seccomp syscall argument for MIPS64
-
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Merge x86 fixes from Ingo Molnar: "Two followup fixes related to the previous LDT fix" Also applied a further FPU emulation fix from Andy Lutomirski to the branch before actually merging it. * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip x86/ldt: Further fix FPU emulation x86/ldt: Correct FPU emulation access to LDT x86/ldt: Correct LDT access in single stepping logic
-
Andy Lutomirski authored
The previous fix confused a selector with a segment prefix. Fix it. Compile-tested only. Cc: stable@vger.kernel.org Cc: Juergen Gross <jgross@suse.com> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Fixes: 4809146b ("x86/ldt: Correct FPU emulation access to LDT") Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Jann Horn authored
fuse_dev_ioctl() performed fuse_get_dev() on a user-supplied fd, leading to a type confusion issue. Fix it by checking file->f_op. Signed-off-by: Jann Horn <jann@thejh.net> Acked-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Olof Johansson authored
Merge tag 'keystone-dts-late-fixes-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/ssantosh/linux-keystone into fixes ARM: Couple of Keysyone MDIO DTS fixes for 4.2-rc6+ These are necessary to get the NIC card working on all Keystone EVMs. Couple of boards are broken without these two fixes. * tag 'keystone-dts-late-fixes-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/ssantosh/linux-keystone: ARM: dts: keystone: Fix the mdio bindings by moving it to soc specific file ARM: dts: keystone: fix the clock node for mdio Signed-off-by: Olof Johansson <olof@lixom.net>
-
Markos Chandras authored
Commit 4c21b8fd ("MIPS: seccomp: Handle indirect system calls (o32)") fixed indirect system calls on O32 but it also introduced a bug for MIPS64 where it erroneously modified the v0 (syscall) register with the assumption that the sycall offset hasn't been taken into consideration. This breaks seccomp on MIPS64 n64 and n32 ABIs. We fix this by replacing the addition with a move instruction. Fixes: 4c21b8fd ("MIPS: seccomp: Handle indirect system calls (o32)") Cc: <stable@vger.kernel.org> # 3.15+ Reviewed-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/10951/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
-
- 15 Aug, 2015 3 commits
-
-
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds authored
Pull SCSI fixes from James Bottomley: "This has two libfc fixes for bugs causing rare crashes, one iscsi fix for a potential hang on shutdown, and a fix for an I/O blocksize issue which caused a regression" * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: sd: Fix maximum I/O size for BLOCK_PC requests libfc: Fix fc_fcp_cleanup_each_cmd() libfc: Fix fc_exch_recv_req() error path libiscsi: Fix host busy blocking during connection teardown
-
git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds authored
Pull KVM fixes from Paolo Bonzini: "Just two very small & simple patches" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: Use adjustment in guest cycles when handling MSR_IA32_TSC_ADJUST KVM: x86: zero IDT limit on entry to SMM
-
Linus Torvalds authored
Merge fixes from Andrew Morton: "11 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: Update maintainers for DRM STI driver mm: cma: mark cma_bitmap_maxno() inline in header zram: fix pool name truncation memory-hotplug: fix wrong edge when hot add a new node .mailmap: Andrey Ryabinin has moved ipc/sem.c: update/correct memory barriers mm/hwpoison: fix panic due to split huge zero page ipc,sem: remove uneeded sem_undo_list lock usage in exit_sem() ipc,sem: fix use after free on IPC_RMID after a task using same semaphore set exits mm/hwpoison: fix fail isolate hugetlbfs page w/ refcount held mm/hwpoison: fix page refcount of unknown non LRU page
-
- 14 Aug, 2015 10 commits
-
-
git://git.kernel.org/pub/scm/linux/kernel/git/clk/linuxLinus Torvalds authored
Pull clock fix from Stephen Boyd: "A one-liner for a regression found in the PXA clock driver" * tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: clk: pxa: pxa3xx: fix CKEN register access
-
Benjamin Gaignard authored
Add Vincent Abriou and myself as maintainers. Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org> Cc: Vincent Abriou <vincent.abriou@st.com> Cc: Dave Airlie <airlied@linux.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Gregory Fong authored
cma_bitmap_maxno() was marked as static and not static inline, which can cause warnings about this function not being used if this file is included in a file that does not call that function, and violates the conventions used elsewhere. The two options are to move the function implementation back to mm/cma.c or make it inline here, and it's simple enough for the latter to make sense. Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Sergey Senozhatsky authored
zram_meta_alloc() constructs a pool name for zs_create_pool() call as snprintf(pool_name, sizeof(pool_name), "zram%d", device_id); However, it defines pool name buffer to be only 8 bytes long (minus trailing zero), which means that we can have only 1000 pool names: zram0 -- zram999. With CONFIG_ZSMALLOC_STAT enabled an attempt to create a device zram1000 can fail if device zram100 already exists, because snprintf() will truncate new pool name to zram100 and pass it debugfs_create_dir(), causing: debugfs dir <zram100> creation failed zram: Error creating memory pool ... and so on. Fix it by passing zram->disk->disk_name to zram_meta_alloc() instead of divice_id. We construct zram%d name earlier and keep it as a ->disk_name, no need to snprintf() it again. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Xishi Qiu authored
When we add a new node, the edge of memory may be wrong. e.g. system has 4 nodes, and node3 is movable, node3 mem:[24G-32G], 1. hotremove the node3, 2. then hotadd node3 with a part of memory, mem:[26G-30G], 3. call hotadd_new_pgdat() free_area_init_node() get_pfn_range_for_nid() 4. it will return wrong start_pfn and end_pfn, because we have not update the memblock. This patch also fixes a BUG_ON during hot-addition, please see http://marc.info/?l=linux-kernel&m=142961156129456&w=2Signed-off-by: Xishi Qiu <qiuxishi@huawei.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Andrey Ryabinin authored
Update my email address. Signed-off-by: Andrey Ryabinin <ryabinin.a.a@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Manfred Spraul authored
sem_lock() did not properly pair memory barriers: !spin_is_locked() and spin_unlock_wait() are both only control barriers. The code needs an acquire barrier, otherwise the cpu might perform read operations before the lock test. As no primitive exists inside <include/spinlock.h> and since it seems noone wants another primitive, the code creates a local primitive within ipc/sem.c. With regards to -stable: The change of sem_wait_array() is a bugfix, the change to sem_lock() is a nop (just a preprocessor redefinition to improve the readability). The bugfix is necessary for all kernels that use sem_wait_array() (i.e.: starting from 3.10). Signed-off-by: Manfred Spraul <manfred@colorfullife.com> Reported-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Kirill Tkhai <ktkhai@parallels.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: <stable@vger.kernel.org> [3.10+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Wanpeng Li authored
Bug: ------------[ cut here ]------------ kernel BUG at mm/huge_memory.c:1957! invalid opcode: 0000 [#1] SMP Modules linked in: snd_hda_codec_hdmi i915 rpcsec_gss_krb5 snd_hda_codec_realtek snd_hda_codec_generic nfsv4 dns_re CPU: 2 PID: 2576 Comm: test_huge Not tainted 4.2.0-rc5-mm1+ #27 Hardware name: Dell Inc. OptiPlex 7020/0F5C5X, BIOS A03 01/08/2015 task: ffff880204e3d600 ti: ffff8800db16c000 task.ti: ffff8800db16c000 RIP: split_huge_page_to_list+0xdb/0x120 Call Trace: memory_failure+0x32e/0x7c0 madvise_hwpoison+0x8b/0x160 SyS_madvise+0x40/0x240 ? do_page_fault+0x37/0x90 entry_SYSCALL_64_fastpath+0x12/0x71 Code: ff f0 41 ff 4c 24 30 74 0d 31 c0 48 83 c4 08 5b 41 5c 41 5d c9 c3 4c 89 e7 e8 e2 58 fd ff 48 83 c4 08 31 c0 RIP split_huge_page_to_list+0xdb/0x120 RSP <ffff8800db16fde8> ---[ end trace aee7ce0df8e44076 ]--- Testcase: #define _GNU_SOURCE #include <stdlib.h> #include <stdio.h> #include <sys/mman.h> #include <unistd.h> #include <fcntl.h> #include <sys/types.h> #include <errno.h> #include <string.h> #define MB 1024*1024 int main(void) { char *mem; posix_memalign((void **)&mem, 2 * MB, 200 * MB); madvise(mem, 200 * MB, MADV_HWPOISON); free(mem); return 0; } Huge zero page is allocated if page fault w/o FAULT_FLAG_WRITE flag. The get_user_pages_fast() which called in madvise_hwpoison() will get huge zero page if the page is not allocated before. Huge zero page is a tranparent huge page, however, it is not an anonymous page. memory_failure will split the huge zero page and trigger BUG_ON(is_huge_zero_page(page)); After commit 98ed2b00 ("mm/memory-failure: give up error handling for non-tail-refcounted thp"), memory_failure will not catch non anon thp from madvise_hwpoison path and this bug occur. Fix it by catching non anon thp in memory_failure in order to not split huge zero page in madvise_hwpoison path. After this patch: Injecting memory failure for page 0x202800 at 0x7fd8ae800000 MCE: 0x202800: non anonymous thp [...] [akpm@linux-foundation.org: remove second split, per Wanpeng] Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Herton R. Krzesinski authored
After we acquire the sma->sem_perm lock in exit_sem(), we are protected against a racing IPC_RMID operation. Also at that point, we are the last user of sem_undo_list. Therefore it isn't required that we acquire or use ulp->lock. Signed-off-by: Herton R. Krzesinski <herton@redhat.com> Acked-by: Manfred Spraul <manfred@colorfullife.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Rafael Aquini <aquini@redhat.com> CC: Aristeu Rozanski <aris@redhat.com> Cc: David Jeffery <djeffery@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Herton R. Krzesinski authored
The current semaphore code allows a potential use after free: in exit_sem we may free the task's sem_undo_list while there is still another task looping through the same semaphore set and cleaning the sem_undo list at freeary function (the task called IPC_RMID for the same semaphore set). For example, with a test program [1] running which keeps forking a lot of processes (which then do a semop call with SEM_UNDO flag), and with the parent right after removing the semaphore set with IPC_RMID, and a kernel built with CONFIG_SLAB, CONFIG_SLAB_DEBUG and CONFIG_DEBUG_SPINLOCK, you can easily see something like the following in the kernel log: Slab corruption (Not tainted): kmalloc-64 start=ffff88003b45c1c0, len=64 000: 6b 6b 6b 6b 6b 6b 6b 6b 00 6b 6b 6b 6b 6b 6b 6b kkkkkkkk.kkkkkkk 010: ff ff ff ff 6b 6b 6b 6b ff ff ff ff ff ff ff ff ....kkkk........ Prev obj: start=ffff88003b45c180, len=64 000: 00 00 00 00 ad 4e ad de ff ff ff ff 5a 5a 5a 5a .....N......ZZZZ 010: ff ff ff ff ff ff ff ff c0 fb 01 37 00 88 ff ff ...........7.... Next obj: start=ffff88003b45c200, len=64 000: 00 00 00 00 ad 4e ad de ff ff ff ff 5a 5a 5a 5a .....N......ZZZZ 010: ff ff ff ff ff ff ff ff 68 29 a7 3c 00 88 ff ff ........h).<.... BUG: spinlock wrong CPU on CPU#2, test/18028 general protection fault: 0000 [#1] SMP Modules linked in: 8021q mrp garp stp llc nf_conntrack_ipv4 nf_defrag_ipv4 ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables binfmt_misc ppdev input_leds joydev parport_pc parport floppy serio_raw virtio_balloon virtio_rng virtio_console virtio_net iosf_mbi crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcspkr qxl ttm drm_kms_helper drm snd_hda_codec_generic i2c_piix4 snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer snd soundcore crc32c_intel virtio_pci virtio_ring virtio pata_acpi ata_generic [last unloaded: speedstep_lib] CPU: 2 PID: 18028 Comm: test Not tainted 4.2.0-rc5+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014 RIP: spin_dump+0x53/0xc0 Call Trace: spin_bug+0x30/0x40 do_raw_spin_unlock+0x71/0xa0 _raw_spin_unlock+0xe/0x10 freeary+0x82/0x2a0 ? _raw_spin_lock+0xe/0x10 semctl_down.clone.0+0xce/0x160 ? __do_page_fault+0x19a/0x430 ? __audit_syscall_entry+0xa8/0x100 SyS_semctl+0x236/0x2c0 ? syscall_trace_leave+0xde/0x130 entry_SYSCALL_64_fastpath+0x12/0x71 Code: 8b 80 88 03 00 00 48 8d 88 60 05 00 00 48 c7 c7 a0 2c a4 81 31 c0 65 8b 15 eb 40 f3 7e e8 08 31 68 00 4d 85 e4 44 8b 4b 08 74 5e <45> 8b 84 24 88 03 00 00 49 8d 8c 24 60 05 00 00 8b 53 04 48 89 RIP [<ffffffff810d6053>] spin_dump+0x53/0xc0 RSP <ffff88003750fd68> ---[ end trace 783ebb76612867a0 ]--- NMI watchdog: BUG: soft lockup - CPU#3 stuck for 22s! [test:18053] Modules linked in: 8021q mrp garp stp llc nf_conntrack_ipv4 nf_defrag_ipv4 ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables binfmt_misc ppdev input_leds joydev parport_pc parport floppy serio_raw virtio_balloon virtio_rng virtio_console virtio_net iosf_mbi crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcspkr qxl ttm drm_kms_helper drm snd_hda_codec_generic i2c_piix4 snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer snd soundcore crc32c_intel virtio_pci virtio_ring virtio pata_acpi ata_generic [last unloaded: speedstep_lib] CPU: 3 PID: 18053 Comm: test Tainted: G D 4.2.0-rc5+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014 RIP: native_read_tsc+0x0/0x20 Call Trace: ? delay_tsc+0x40/0x70 __delay+0xf/0x20 do_raw_spin_lock+0x96/0x140 _raw_spin_lock+0xe/0x10 sem_lock_and_putref+0x11/0x70 SYSC_semtimedop+0x7bf/0x960 ? handle_mm_fault+0xbf6/0x1880 ? dequeue_task_fair+0x79/0x4a0 ? __do_page_fault+0x19a/0x430 ? kfree_debugcheck+0x16/0x40 ? __do_page_fault+0x19a/0x430 ? __audit_syscall_entry+0xa8/0x100 ? do_audit_syscall_entry+0x66/0x70 ? syscall_trace_enter_phase1+0x139/0x160 SyS_semtimedop+0xe/0x10 SyS_semop+0x10/0x20 entry_SYSCALL_64_fastpath+0x12/0x71 Code: 47 10 83 e8 01 85 c0 89 47 10 75 08 65 48 89 3d 1f 74 ff 7e c9 c3 0f 1f 44 00 00 55 48 89 e5 e8 87 17 04 00 66 90 c9 c3 0f 1f 00 <55> 48 89 e5 0f 31 89 c1 48 89 d0 48 c1 e0 20 89 c9 48 09 c8 c9 Kernel panic - not syncing: softlockup: hung tasks I wasn't able to trigger any badness on a recent kernel without the proper config debugs enabled, however I have softlockup reports on some kernel versions, in the semaphore code, which are similar as above (the scenario is seen on some servers running IBM DB2 which uses semaphore syscalls). The patch here fixes the race against freeary, by acquiring or waiting on the sem_undo_list lock as necessary (exit_sem can race with freeary, while freeary sets un->semid to -1 and removes the same sem_undo from list_proc or when it removes the last sem_undo). After the patch I'm unable to reproduce the problem using the test case [1]. [1] Test case used below: #include <stdio.h> #include <sys/types.h> #include <sys/ipc.h> #include <sys/sem.h> #include <sys/wait.h> #include <stdlib.h> #include <time.h> #include <unistd.h> #include <errno.h> #define NSEM 1 #define NSET 5 int sid[NSET]; void thread() { struct sembuf op; int s; uid_t pid = getuid(); s = rand() % NSET; op.sem_num = pid % NSEM; op.sem_op = 1; op.sem_flg = SEM_UNDO; semop(sid[s], &op, 1); exit(EXIT_SUCCESS); } void create_set() { int i, j; pid_t p; union { int val; struct semid_ds *buf; unsigned short int *array; struct seminfo *__buf; } un; /* Create and initialize semaphore set */ for (i = 0; i < NSET; i++) { sid[i] = semget(IPC_PRIVATE , NSEM, 0644 | IPC_CREAT); if (sid[i] < 0) { perror("semget"); exit(EXIT_FAILURE); } } un.val = 0; for (i = 0; i < NSET; i++) { for (j = 0; j < NSEM; j++) { if (semctl(sid[i], j, SETVAL, un) < 0) perror("semctl"); } } /* Launch threads that operate on semaphore set */ for (i = 0; i < NSEM * NSET * NSET; i++) { p = fork(); if (p < 0) perror("fork"); if (p == 0) thread(); } /* Free semaphore set */ for (i = 0; i < NSET; i++) { if (semctl(sid[i], NSEM, IPC_RMID)) perror("IPC_RMID"); } /* Wait for forked processes to exit */ while (wait(NULL)) { if (errno == ECHILD) break; }; } int main(int argc, char **argv) { pid_t p; srand(time(NULL)); while (1) { p = fork(); if (p < 0) { perror("fork"); exit(EXIT_FAILURE); } if (p == 0) { create_set(); goto end; } /* Wait for forked processes to exit */ while (wait(NULL)) { if (errno == ECHILD) break; }; } end: return 0; } [akpm@linux-foundation.org: use normal comment layout] Signed-off-by: Herton R. Krzesinski <herton@redhat.com> Acked-by: Manfred Spraul <manfred@colorfullife.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Rafael Aquini <aquini@redhat.com> CC: Aristeu Rozanski <aris@redhat.com> Cc: David Jeffery <djeffery@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-