Hi Ming, On 2019-02-21 11:16, Ming Lei wrote: > On Thu, Feb 21, 2019 at 11:08:19AM +0100, Marek Szyprowski wrote: >> On 2019-02-21 10:57, Ming Lei wrote: >>> On Thu, Feb 21, 2019 at 09:42:59AM +0100, Marek Szyprowski wrote: >>>> On 2019-02-15 12:13, Ming Lei wrote: >>>>> This patch pulls the trigger for multi-page bvecs. >>>>> >>>>> Reviewed-by: Omar Sandoval <osandov@xxxxxx> >>>>> Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> >>>> Since Linux next-20190218 I've observed problems with block layer on one >>>> of my test devices (Odroid U3 with EXT4 rootfs on SD card). Bisecting >>>> this issue led me to this change. This is also the first linux-next >>>> release with this change merged. The issue is fully reproducible and can >>>> be observed in the following kernel log: >>>> >>>> sdhci: Secure Digital Host Controller Interface driver >>>> sdhci: Copyright(c) Pierre Ossman >>>> s3c-sdhci 12530000.sdhci: clock source 2: mmc_busclk.2 (100000000 Hz) >>>> s3c-sdhci 12530000.sdhci: Got CD GPIO >>>> mmc0: SDHCI controller on samsung-hsmmc [12530000.sdhci] using ADMA >>>> mmc0: new high speed SDHC card at address aaaa >>>> mmcblk0: mmc0:aaaa SL16G 14.8 GiB >>>> >>>> ... >>>> >>>> EXT4-fs (mmcblk0p2): INFO: recovery required on readonly filesystem >>>> EXT4-fs (mmcblk0p2): write access will be enabled during recovery >>>> EXT4-fs (mmcblk0p2): recovery complete >>>> EXT4-fs (mmcblk0p2): mounted filesystem with ordered data mode. Opts: (null) >>>> VFS: Mounted root (ext4 filesystem) readonly on device 179:2. >>>> devtmpfs: mounted >>>> Freeing unused kernel memory: 1024K >>>> hub 1-3:1.0: USB hub found >>>> Run /sbin/init as init process >>>> hub 1-3:1.0: 3 ports detected >>>> *** stack smashing detected ***: <unknown> terminated >>>> Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000004 >>>> CPU: 1 PID: 1 Comm: init Not tainted 5.0.0-rc6-next-20190218 #1546 >>>> Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) >>>> [<c01118d0>] (unwind_backtrace) from [<c010d794>] (show_stack+0x10/0x14) >>>> [<c010d794>] (show_stack) from [<c09ff8a4>] (dump_stack+0x90/0xc8) >>>> [<c09ff8a4>] (dump_stack) from [<c0125944>] (panic+0xfc/0x304) >>>> [<c0125944>] (panic) from [<c012bc98>] (do_exit+0xabc/0xc6c) >>>> [<c012bc98>] (do_exit) from [<c012c100>] (do_group_exit+0x3c/0xbc) >>>> [<c012c100>] (do_group_exit) from [<c0138908>] (get_signal+0x130/0xbf4) >>>> [<c0138908>] (get_signal) from [<c010c7a0>] (do_work_pending+0x130/0x618) >>>> [<c010c7a0>] (do_work_pending) from [<c0101034>] >>>> (slow_work_pending+0xc/0x20) >>>> Exception stack(0xe88c3fb0 to 0xe88c3ff8) >>>> 3fa0: 00000000 bea7787c 00000005 >>>> b6e8d0b8 >>>> 3fc0: bea77a18 b6f92010 b6e8d0b8 00000001 b6e8d0c8 00000001 b6e8c000 >>>> bea77b60 >>>> 3fe0: 00000020 bea77998 ffffffff b6d52368 60000050 ffffffff >>>> CPU3: stopping >>>> >>>> I would like to help debugging and fixing this issue, but I don't really >>>> have idea where to start. Here are some more detailed information about >>>> my test system: >>>> >>>> 1. Board: ARM 32bit Samsung Exynos4412-based Odroid U3 (device tree >>>> source: arch/arm/boot/dts/exynos4412-odroidu3.dts) >>>> >>>> 2. Block device: MMC/SDHCI/SDHCI-S3C with SD card >>>> (drivers/mmc/host/sdhci-s3c.c driver, sdhci_2 device node in the device >>>> tree) >>>> >>>> 3. Rootfs: Ext4 >>>> >>>> 4. Kernel config: arch/arm/configs/exynos_defconfig >>>> >>>> I can gather more logs if needed, just let me which kernel option to >>>> enable. Reverting this commit on top of next-20190218 as well as current >>>> linux-next (tested with next-20190221) fixes this issue and makes the >>>> system bootable again. >>> Could you test the patch in following link and see if it can make a difference? >>> >>> https://marc.info/?l=linux-aio&m=155070355614541&w=2 >> I've tested that patch, but it doesn't make any difference on the test >> system. In the log I see no warning added by it. > I guess it might be related with memory corruption, could you enable the > following debug options and post the dmesg log? > > CONFIG_DEBUG_STACKOVERFLOW=y > CONFIG_KASAN=y It won't be that easy as none of the above options is available on ARM 32bit. I will try to apply some ARM KASAN patches floating on the net and let you know the result. Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland
