Hi, Today's next fails to mount NFS root under my ARM targets and fails to mount root from file image under QMU. [ 21.512866] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 21.695484] [<c03bcc04>] (nfs_fs_mount) from [<c02cf6a4>] (legacy_get_tree+0x34/0xec) [ 21.703225] [<c02cf6a4>] (legacy_get_tree) from [<c029442c>] (vfs_get_tree+0x64/0x180) [ 21.711119] [<c029442c>] (vfs_get_tree) from [<c02b9140>] (do_mount+0x21c/0x958) [ 21.718478] [<c02b9140>] (do_mount) from [<c02b9c38>] (ksys_mount+0x8c/0xbc) [ 21.725513] [<c02b9c38>] (ksys_mount) from [<c0101000>] (ret_fast_syscall+0x0/0x28) Full log from ARM (NFS root): https://krzk.eu/#/builders/25/builds/750/steps/12/logs/serial0 The NFS root failure bisected to: bae551929c5433bd56ec4dcb97c7d4a50153d357 is the first bad commit commit bae551929c5433bd56ec4dcb97c7d4a50153d357 Author: David Howells <dhowells@xxxxxxxxxx> Date: Tue Jul 10 21:43:37 2018 +0100 vfs: Separate changing mount flags full remount Separate just the changing of mount flags (MS_REMOUNT|MS_BIND) from full remount because the mount data will get parsed with the new fs_context stuff prior to doing a remount - and this causes the syscall to fail under some circumstances. The QEMU issue seems slightly different and I did not bisect it. The QEMU just cannot find rootfs: [ 1.008052] Filesystem requires source device [ 1.008513] VFS: Cannot open root device "mmcblk0" or unknown-block(179,0): error -2 [ 1.008790] Please append a correct "root=" boot option; here are the available partitions: [ 1.009300] 0100 16384 ram0 [ 1.009337] (driver?) [ 1.009806] fe00 5120 vda [ 1.009843] driver: virtio_blk [ 1.010296] b300 110592 mmcblk0 [ 1.010319] driver: mmcblk [ 1.010859] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(179,0) [ 1.011580] ---[ end Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(179,0) ]--- Boards config: 1. Arch ARM Linux 2. exynos_defconfig - Odroid HC1 ARMv7, octa-core (Cortex-A7+A15), Exynos5422 SoC Systemd: v239 - Odroid U3 ARMv7, quad-core, Exynos4412 SoC Systemd: v238 - Odroid XU ARMv7, octa-core (Cortex-A7+A15) but only A15 working, Exynos5410 SoC Systemd: v236 - Odroid XU3 ARMv7, octa-core (Cortex-A7+A15), Exynos5422 SoC Systemd: v236 3. Custom VF50 defconfig - Toradex Colibri VF50 on Iris board ARMv7, UP, Cortext-A5, NXP VF500 Systemd: v232 4. All boards boot from TFTP with NFS root (NFSv4) 5. QEMU ARMv7, vexpress-v2p-ca9, 128 MB RAM Best regards, Krzysztof
