Buildresult: linus/se7619_defconfig/sh4-gcc10 built on Mar 11 2021, 07:21

kisskb

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Status:	OK
Date/Time:	Mar 11 2021, 07:21
Duration:	0:00:35.013102
Builder:	blade46
Revision:	Merge tag 'for-linus-2021-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux (`d3110f256d126b44d34c1f662310cd295877c447)`
Target:	linus/se7619_defconfig/sh4-gcc10
Branch:	linus
Compiler:	sh4-gcc10 (sh4-linux-gcc (GCC) 10.1.0 / GNU ld (GNU Binutils) 2.34)
Config:	se7619_defconfig (download)
Log:	Download original Possible warnings (7) <stdin>:1511:2: warning: #warning syscall clone3 not implemented [-Wcpp] include/linux/sh_intc.h:100:63: warning: division 'sizeof (void ) / sizeof (void)' does not compute the number of array elements [-Wsizeof-pointer-div] include/linux/sh_intc.h:100:63: warning: division 'sizeof (void ) / sizeof (void)' does not compute the number of array elements [-Wsizeof-pointer-div] include/linux/sh_intc.h:100:63: warning: division 'sizeof (void ) / sizeof (void)' does not compute the number of array elements [-Wsizeof-pointer-div] include/linux/sh_intc.h:100:63: warning: division 'sizeof (void ) / sizeof (void)' does not compute the number of array elements [-Wsizeof-pointer-div] arch/sh/kernel/traps.c:183:15: warning: unused variable 'cpu' [-Wunused-variable] drivers/tty/serial/sh-sci.c:2677:19: warning: unused variable 'sport' [-Wunused-variable] Full Log # git rev-parse -q --verify d3110f256d126b44d34c1f662310cd295877c447^{commit} d3110f256d126b44d34c1f662310cd295877c447 already have revision, skipping fetch # git checkout -q -f -B kisskb d3110f256d126b44d34c1f662310cd295877c447 # git clean -qxdf # < git log -1 # commit d3110f256d126b44d34c1f662310cd295877c447 # Merge: d0df9aabefda ee2e3f50629f # Author: Linus Torvalds <torvalds@linux-foundation.org> # Date: Wed Mar 10 10:01:35 2021 -0800 # # Merge tag 'for-linus-2021-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux # # Pull detached mounts fix from Christian Brauner: # "Creating a series of detached mounts, attaching them to the # filesystem, and unmounting them can be used to trigger an integer # overflow in ns->mounts causing the kernel to block any new mounts in # count_mounts() and returning ENOSPC because it falsely assumes that # the maximum number of mounts in the mount namespace has been reached, # i.e. it thinks it can't fit the new mounts into the mount namespace # anymore. # # Without this fix heavy use of the new mount API with move_mount() will # cause the host to become unuseable and thus blocks some xfstest # patches I want to resend. # # Depending on the number of mounts in your system, this can be # reproduced on any kernel that supportes open_tree() and move_mount(). # # A reproducer has been sent for inclusion with xfstests. It takes care # to do this in another mount namespace, not in the host's mount # namespace so there shouldn't be any risk in running it but if one did # run it on the host it would require a reboot in order to be able to # mount again. See # # https://lore.kernel.org/fstests/20210309121041.753359-1-christian.brauner@ubuntu.com # # The root cause of this is that detached mounts aren't handled # correctly when source and target mount are identical and reside on a # shared mount causing a broken mount tree where the detached source # itself is propagated which propagation prevents for regular # bind-mounts and new mounts. # # This ultimately leads to a miscalculation of the number of mounts in # the mount namespace. # # Detached mounts created via 'open_tree(fd, path, OPEN_TREE_CLONE)' are # essentially like an unattached bind-mount. They can then later on be # attached to the filesystem via move_mount() which calls into # attach_recursive_mount(). # # Part of attaching it to the filesystem is making sure that mounts get # correctly propagated in case the destination mountpoint is MS_SHARED, # i.e. is a shared mountpoint. This is done by calling into # propagate_mnt() which walks the list of peers calling propagate_one() # on each mount in this list making sure it receives the propagation # event. The propagate_one() function thereby skips both new mounts and # bind mounts to not propagate them "into themselves". Both are # identified by checking whether the mount is already attached to any # mount namespace in mnt->mnt_ns. The is what the IS_MNT_NEW() helper is # responsible for. # # However, detached mounts have an anonymous mount namespace attached to # them stashed in mnt->mnt_ns which means that IS_MNT_NEW() doesn't # realize they need to be skipped causing the mount to propagate "into # itself" breaking the mount table and causing a disconnect between the # number of mounts recorded as being beneath or reachable from the # target mountpoint and the number of mounts actually recorded/counted # in ns->mounts ultimately causing an overflow which in turn prevents # any new mounts via the ENOSPC issue. # # So teach propagation to handle detached mounts by making it aware of # them. I've been tracking this issue down for the last couple of days # and then verifying that the fix is correct by unmounting everything in # my current mount table leaving only /proc and /sys mounted and running # the reproducer above overnight verifying the number of mounts counted # in ns->mounts. With this fix the counts are correct and the ENOSPC # issue can't be reproduced. # # This change will only have an effect on mounts created with the new # mount API since detached mounts cannot be created with the old mount # API so regressions are extremely unlikely. # # Here's an illustration: # # #### mount(): # ubuntu@f1-vm:~$ sudo mount --bind /mnt/ /mnt/ # ubuntu@f1-vm:~$ findmnt \| grep -i mnt # ├─/mnt /dev/sda2[/mnt] ext4 rw,relatime # # #### open_tree(OPEN_TREE_CLONE) + move_mount() with bug: # ubuntu@f1-vm:~$ sudo ./mount-new /mnt/ /mnt/ # ubuntu@f1-vm:~$ findmnt \| grep -i mnt # ├─/mnt /dev/sda2[/mnt] ext4 rw,relatime # │ └─/mnt /dev/sda2[/mnt] ext4 rw,relatime # # #### open_tree(OPEN_TREE_CLONE) + move_mount() with the fix: # ubuntu@f1-vm:~$ sudo ./mount-new /mnt /mnt # ubuntu@f1-vm:~$ findmnt \| grep -i mnt # └─/mnt /dev/sda2[/mnt] ext4 rw,relatime" # # * tag 'for-linus-2021-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: # mount: fix mounting of detached mounts onto targets that reside on shared mounts # < /opt/cross/kisskb/korg/gcc-10.1.0-nolibc/sh4-linux/bin/sh4-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-10.1.0-nolibc/sh4-linux/bin/sh4-linux-ld --version # < git log --format=%s --max-count=1 d3110f256d126b44d34c1f662310cd295877c447 # < make -s -j 32 ARCH=sh O=/kisskb/build/linus_se7619_defconfig_sh4-gcc10 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-10.1.0-nolibc/sh4-linux/bin/sh4-linux- se7619_defconfig # < make -s -j 32 ARCH=sh O=/kisskb/build/linus_se7619_defconfig_sh4-gcc10 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-10.1.0-nolibc/sh4-linux/bin/sh4-linux- help # make -s -j 32 ARCH=sh O=/kisskb/build/linus_se7619_defconfig_sh4-gcc10 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-10.1.0-nolibc/sh4-linux/bin/sh4-linux- olddefconfig # make -s -j 32 ARCH=sh O=/kisskb/build/linus_se7619_defconfig_sh4-gcc10 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-10.1.0-nolibc/sh4-linux/bin/sh4-linux- Generating include/generated/machtypes.h <stdin>:1511:2: warning: #warning syscall clone3 not implemented [-Wcpp] In file included from /kisskb/src/arch/sh/include/asm/hw_irq.h:6, from /kisskb/src/include/linux/irq.h:589, from /kisskb/src/include/asm-generic/hardirq.h:17, from /kisskb/src/arch/sh/include/asm/hardirq.h:9, from /kisskb/src/include/linux/hardirq.h:10, from /kisskb/src/include/linux/interrupt.h:11, from /kisskb/src/include/linux/serial_core.h:13, from /kisskb/src/include/linux/serial_sci.h:6, from /kisskb/src/arch/sh/kernel/cpu/sh2/setup-sh7619.c:11: /kisskb/src/include/linux/sh_intc.h:100:63: warning: division 'sizeof (void ) / sizeof (void)' does not compute the number of array elements [-Wsizeof-pointer-div] 100 \| #define _INTC_ARRAY(a) a, __same_type(a, NULL) ? 0 : sizeof(a)/sizeof(a) \| ^ /kisskb/src/include/linux/sh_intc.h:105:24: note: in expansion of macro '_INTC_ARRAY' 105 \| _INTC_ARRAY(vectors), _INTC_ARRAY(groups), \ \| ^~~~~~~~~~~ /kisskb/src/include/linux/sh_intc.h:124:8: note: in expansion of macro 'INTC_HW_DESC' 124 \| .hw = INTC_HW_DESC(vectors, groups, mask_regs, \ \| ^~~~~~~~~~~~ /kisskb/src/arch/sh/kernel/cpu/sh2/setup-sh7619.c:58:8: note: in expansion of macro 'DECLARE_INTC_DESC' 58 \| static DECLARE_INTC_DESC(intc_desc, "sh7619", vectors, NULL, \| ^~~~~~~~~~~~~~~~~ /kisskb/src/include/linux/sh_intc.h:100:63: warning: division 'sizeof (void ) / sizeof (void)' does not compute the number of array elements [-Wsizeof-pointer-div] 100 \| #define _INTC_ARRAY(a) a, __same_type(a, NULL) ? 0 : sizeof(a)/sizeof(a) \| ^ /kisskb/src/include/linux/sh_intc.h:106:2: note: in expansion of macro '_INTC_ARRAY' 106 \| _INTC_ARRAY(mask_regs), _INTC_ARRAY(prio_regs), \ \| ^~~~~~~~~~~ /kisskb/src/include/linux/sh_intc.h:124:8: note: in expansion of macro 'INTC_HW_DESC' 124 \| .hw = INTC_HW_DESC(vectors, groups, mask_regs, \ \| ^~~~~~~~~~~~ /kisskb/src/arch/sh/kernel/cpu/sh2/setup-sh7619.c:58:8: note: in expansion of macro 'DECLARE_INTC_DESC' 58 \| static DECLARE_INTC_DESC(intc_desc, "sh7619", vectors, NULL, \| ^~~~~~~~~~~~~~~~~ /kisskb/src/include/linux/sh_intc.h:100:63: warning: division 'sizeof (void ) / sizeof (void)' does not compute the number of array elements [-Wsizeof-pointer-div] 100 \| #define _INTC_ARRAY(a) a, __same_type(a, NULL) ? 0 : sizeof(a)/sizeof(a) \| ^ /kisskb/src/include/linux/sh_intc.h:107:2: note: in expansion of macro '_INTC_ARRAY' 107 \| _INTC_ARRAY(sense_regs), _INTC_ARRAY(ack_regs), \ \| ^~~~~~~~~~~ /kisskb/src/include/linux/sh_intc.h:124:8: note: in expansion of macro 'INTC_HW_DESC' 124 \| .hw = INTC_HW_DESC(vectors, groups, mask_regs, \ \| ^~~~~~~~~~~~ /kisskb/src/arch/sh/kernel/cpu/sh2/setup-sh7619.c:58:8: note: in expansion of macro 'DECLARE_INTC_DESC' 58 \| static DECLARE_INTC_DESC(intc_desc, "sh7619", vectors, NULL, \| ^~~~~~~~~~~~~~~~~ /kisskb/src/include/linux/sh_intc.h:100:63: warning: division 'sizeof (void ) / sizeof (void)' does not compute the number of array elements [-Wsizeof-pointer-div] 100 \| #define _INTC_ARRAY(a) a, __same_type(a, NULL) ? 0 : sizeof(a)/sizeof(a) \| ^ /kisskb/src/include/linux/sh_intc.h:107:27: note: in expansion of macro '_INTC_ARRAY' 107 \| _INTC_ARRAY(sense_regs), _INTC_ARRAY(ack_regs), \ \| ^~~~~~~~~~~ /kisskb/src/include/linux/sh_intc.h:124:8: note: in expansion of macro 'INTC_HW_DESC' 124 \| .hw = INTC_HW_DESC(vectors, groups, mask_regs, \ \| ^~~~~~~~~~~~ /kisskb/src/arch/sh/kernel/cpu/sh2/setup-sh7619.c:58:8: note: in expansion of macro 'DECLARE_INTC_DESC' 58 \| static DECLARE_INTC_DESC(intc_desc, "sh7619", vectors, NULL, \| ^~~~~~~~~~~~~~~~~ /kisskb/src/arch/sh/kernel/traps.c: In function 'nmi_trap_handler': /kisskb/src/arch/sh/kernel/traps.c:183:15: warning: unused variable 'cpu' [-Wunused-variable] 183 \| unsigned int cpu = smp_processor_id(); \| ^~~ /kisskb/src/drivers/tty/serial/sh-sci.c: In function 'sci_remap_port': /kisskb/src/drivers/tty/serial/sh-sci.c:2677:19: warning: unused variable 'sport' [-Wunused-variable] 2677 \| struct sci_port *sport = to_sci_port(port); \| ^~~~~ Completed OK # rm -rf /kisskb/build/linus_se7619_defconfig_sh4-gcc10 # Build took: 0:00:35.013102

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