Hi Ming, On 2019-02-28 00:29, Ming Lei wrote: > On Wed, Feb 27, 2019 at 08:47:09PM +0000, Jon Hunter wrote: >> On 21/02/2019 08:42, 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 >> I have also noticed some failures when writing to an eMMC device on one >> of our Tegra boards. We have a simple eMMC write/read test and it is >> currently failing because the data written does not match the source. >> >> I did not seem the same crash as reported here, however, in our case the >> rootfs is NFS mounted and so probably would not. However, the bisect >> points to this commit and reverting on top of -next fixes the issues. > It is sdhci, probably related with max segment size, could you test the > following patch: > > https://marc.info/?l=linux-mmc&m=155128334122951&w=2 This seems to be fixing my issue too! Thanks! It also fixed the boot issue from USB stick (Exynos EHCI / Mass Storage), but I suspect that reading the partition table from the sd card (which hold the bootloader and thus must be present to boot the device) was enough to trash memory/page cache and break the boot process. Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland