This is a note to let you know that I've just added the patch titled s390: TASK_SIZE for kernel threads to the 4.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: s390-task_size-for-kernel-threads.patch and it can be found in the queue-4.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From fb94a687d96c570d46332a4a890f1dcb7310e643 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Date: Fri, 24 Feb 2017 07:43:51 +0100 Subject: s390: TASK_SIZE for kernel threads From: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> commit fb94a687d96c570d46332a4a890f1dcb7310e643 upstream. Return a sensible value if TASK_SIZE if called from a kernel thread. This gets us around an issue with copy_mount_options that does a magic size calculation "TASK_SIZE - (unsigned long)data" while in a kernel thread and data pointing to kernel space. Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/s390/include/asm/processor.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -89,7 +89,8 @@ extern void execve_tail(void); * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit. */ -#define TASK_SIZE_OF(tsk) ((tsk)->mm->context.asce_limit) +#define TASK_SIZE_OF(tsk) ((tsk)->mm ? \ + (tsk)->mm->context.asce_limit : TASK_MAX_SIZE) #define TASK_UNMAPPED_BASE (test_thread_flag(TIF_31BIT) ? \ (1UL << 30) : (1UL << 41)) #define TASK_SIZE TASK_SIZE_OF(current) Patches currently in stable-queue which might be from schwidefsky@xxxxxxxxxx are queue-4.10/s390-kdump-use-linux-elf-note-name-instead-of-core.patch queue-4.10/s390-dcssblk-fix-device-size-calculation-in-dcssblk_direct_access.patch queue-4.10/s390-task_size-for-kernel-threads.patch queue-4.10/kvm-s390-disable-dirty-log-retrieval-for-ucontrol-guests.patch queue-4.10/s390-use-correct-input-data-address-for-setup_randomness.patch queue-4.10/s390-topology-correct-allocation-of-topology-information.patch queue-4.10/s390-make-setup_randomness-work.patch queue-4.10/s390-chsc-add-exception-handler-for-chsc-instruction.patch queue-4.10/s390-qdio-clear-dsci-prior-to-scanning-multiple-input-queues.patch