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Linux kernel
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several of them using the Restructured Text markup notation.
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the problems which may result by upgrading your kernel.
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Pull ARM fixes from Russell King:
"A small number of ARM fixes
- Fix function tracer and unwinder dependencies so that we don't end
up building kernels that will crash
- Fix ARMv7M nommu initialisation (missing register initialisation)
- Fix EFI decompressor entry (ensuring barrier instructions are
enabled prior to use)"
* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: 8857/1: efi: enable CP15 DMB instructions before cleaning the cache
ARM: 8856/1: NOMMU: Fix CCR register faulty initialization when MPU is disabled
ARM: fix function graph tracer and unwinder dependencies
Pull powerpc fixes from Michael Ellerman:
"A one-liner to make our Radix MMU support depend on HUGETLB_PAGE. We
use some of the hugetlb inlines (eg. pud_huge()) when operating on the
linear mapping and if they're compiled into empty wrappers we can
corrupt memory.
Then two fixes to our VFIO IOMMU code. The first is not a regression
but fixes the locking to avoid a user-triggerable deadlock.
The second does fix a regression since rc1, and depends on the first
fix. It makes it possible to run guests with large amounts of memory
again (~256GB).
Thanks to Alexey Kardashevskiy"
* tag 'powerpc-5.1-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/mm_iommu: Allow pinning large regions
powerpc/mm_iommu: Fix potential deadlock
powerpc/mm/radix: Make Radix require HUGETLB_PAGE
The EFI stub is entered with the caches and MMU enabled by the
firmware, and once the stub is ready to hand over to the decompressor,
we clean and disable the caches.
The cache clean routines use CP15 barrier instructions, which can be
disabled via SCTLR. Normally, when using the provided cache handling
routines to enable the caches and MMU, this bit is enabled as well.
However, but since we entered the stub with the caches already enabled,
this routine is not executed before we call the cache clean routines,
resulting in undefined instruction exceptions if the firmware never
enabled this bit.
So set the bit explicitly in the EFI entry code, but do so in a way that
guarantees that the resulting code can still run on v6 cores as well
(which are guaranteed to have CP15 barriers enabled)
Cc: <stable@vger.kernel.org> # v4.9+
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Pull block fixes from Jens Axboe:
"A set of io_uring fixes that should go into this release. In
particular, this contains:
- The mutex lock vs ctx ref count fix (me)
- Removal of a dead variable (me)
- Two race fixes (Stefan)
- Ring head/tail condition fix for poll full SQ detection (Stefan)"
* tag 'for-linus-20190428' of git://git.kernel.dk/linux-block:
io_uring: remove 'state' argument from io_{read,write} path
io_uring: fix poll full SQ detection
io_uring: fix race condition when sq threads goes sleeping
io_uring: fix race condition reading SQ entries
io_uring: fail io_uring_register(2) on a dying io_uring instance
When called with vmas_arg==NULL, get_user_pages_longterm() allocates
an array of nr_pages*8 which can easily get greater that the max order,
for example, registering memory for a 256GB guest does this and fails
in __alloc_pages_nodemask().
This adds a loop over chunks of entries to fit the max order limit.
Fixes: 678e174c4c16 ("powerpc/mm/iommu: allow migration of cma allocated pages during mm_iommu_do_alloc", 2019-03-05)
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When CONFIG_ARM_MPU is not defined, the base address of v7M SCB register
is not initialized with correct value. This prevents enabling I/D caches
when the L1 cache poilcy is applied in kernel.
Fixes: 3c24121039c9da14692eb48f6e39565b28c0f3cf ("ARM: 8756/1: NOMMU: Postpone MPU activation till __after_proc_init")
Signed-off-by: Tigran Tadevosyan <tigran.tadevosyan@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Pull rdma fixes from Jason Gunthorpe:
"One core bug fix and a few driver ones
- FRWR memory registration for hfi1/qib didn't work with with some
iovas causing a NFSoRDMA failure regression due to a fix in the NFS
side
- A command flow error in mlx5 allowed user space to send a corrupt
command (and also smash the kernel stack we've since learned)
- Fix a regression and some bugs with device hot unplug that was
discovered while reviewing Andrea's patches
- hns has a failure if the user asks for certain QP configurations"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
RDMA/hns: Bugfix for mapping user db
RDMA/ucontext: Fix regression with disassociate
RDMA/mlx5: Use rdma_user_map_io for mapping BAR pages
RDMA/mlx5: Do not allow the user to write to the clock page
IB/mlx5: Fix scatter to CQE in DCT QP creation
IB/rdmavt: Fix frwr memory registration
Since commit 09bb839434b we don't use the state argument for any sort
of on-stack caching in the io read and write path. Remove the stale
and unused argument from them, and bubble it up to __io_submit_sqe()
and down to io_prep_rw().
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently mm_iommu_do_alloc() is called in 2 cases:
- VFIO_IOMMU_SPAPR_REGISTER_MEMORY ioctl() for normal memory:
this locks &mem_list_mutex and then locks mm::mmap_sem
several times when adjusting locked_vm or pinning pages;
- vfio_pci_nvgpu_regops::mmap() for GPU memory:
this is called with mm::mmap_sem held already and it locks
&mem_list_mutex.
So one can craft a userspace program to do special ioctl and mmap in
2 threads concurrently and cause a deadlock which lockdep warns about
(below).
We did not hit this yet because QEMU constructs the machine in a single
thread.
This moves the overlap check next to where the new entry is added and
reduces the amount of time spent with &mem_list_mutex held.
This moves locked_vm adjustment from under &mem_list_mutex.
This relies on mm_iommu_adjust_locked_vm() doing nothing when entries==0.
This is one of the lockdep warnings:
======================================================
WARNING: possible circular locking dependency detected
5.1.0-rc2-le_nv2_aikATfstn1-p1 #363 Not tainted
------------------------------------------------------
qemu-system-ppc/8038 is trying to acquire lock:
000000002ec6c453 (mem_list_mutex){+.+.}, at: mm_iommu_do_alloc+0x70/0x490
but task is already holding lock:
00000000fd7da97f (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0xf0/0x160
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&mm->mmap_sem){++++}:
lock_acquire+0xf8/0x260
down_write+0x44/0xa0
mm_iommu_adjust_locked_vm.part.1+0x4c/0x190
mm_iommu_do_alloc+0x310/0x490
tce_iommu_ioctl.part.9+0xb84/0x1150 [vfio_iommu_spapr_tce]
vfio_fops_unl_ioctl+0x94/0x430 [vfio]
do_vfs_ioctl+0xe4/0x930
ksys_ioctl+0xc4/0x110
sys_ioctl+0x28/0x80
system_call+0x5c/0x70
-> #0 (mem_list_mutex){+.+.}:
__lock_acquire+0x1484/0x1900
lock_acquire+0xf8/0x260
__mutex_lock+0x88/0xa70
mm_iommu_do_alloc+0x70/0x490
vfio_pci_nvgpu_mmap+0xc0/0x130 [vfio_pci]
vfio_pci_mmap+0x198/0x2a0 [vfio_pci]
vfio_device_fops_mmap+0x44/0x70 [vfio]
mmap_region+0x5d4/0x770
do_mmap+0x42c/0x650
vm_mmap_pgoff+0x124/0x160
ksys_mmap_pgoff+0xdc/0x2f0
sys_mmap+0x40/0x80
system_call+0x5c/0x70
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&mm->mmap_sem);
lock(mem_list_mutex);
lock(&mm->mmap_sem);
lock(mem_list_mutex);
*** DEADLOCK ***
1 lock held by qemu-system-ppc/8038:
#0: 00000000fd7da97f (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0xf0/0x160
Fixes: c10c21efa4bc ("powerpc/vfio/iommu/kvm: Do not pin device memory", 2018-12-19)
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Naresh Kamboju recently reported that the function-graph tracer crashes
on ARM. The function-graph tracer assumes that the kernel is built with
frame pointers.
We explicitly disabled the function-graph tracer when building Thumb2,
since the Thumb2 ABI doesn't have frame pointers.
We recently changed the way the unwinder method was selected, which
seems to have made it more likely that we can end up with the function-
graph tracer enabled but without the kernel built with frame pointers.
Fix up the function graph tracer dependencies so the option is not
available when we have no possibility of having frame pointers, and
adjust the dependencies on the unwinder option to hide the non-frame
pointer unwinder options if the function-graph tracer is enabled.
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Pull dmaengine fixes from Vinod Koul:
- fix for wrong register use in mediatek driver
- fix in sh driver for glitch is tx_status and treating 0 a valid
residue for cyclic
- fix in bcm driver for using right memory allocation flag
* tag 'dmaengine-fix-5.1-rc7' of git://git.infradead.org/users/vkoul/slave-dma:
dmaengine: mediatek-cqdma: fix wrong register usage in mtk_cqdma_start
dmaengine: sh: rcar-dmac: Fix glitch in dmaengine_tx_status
dmaengine: sh: rcar-dmac: With cyclic DMA residue 0 is valid
dmaengine: bcm2835: Avoid GFP_KERNEL in device_prep_slave_sg
When the maximum send wr delivered by the user is zero, the qp does not
have a sq.
When allocating the sq db buffer to store the user sq pi pointer and map
it to the kernel mode, max_send_wr is used as the trigger condition, while
the kernel does not consider the max_send_wr trigger condition when
mapmping db. It will cause sq record doorbell map fail and create qp fail.
The failed print information as follows:
hns3 0000:7d:00.1: Send cmd: tail - 418, opcode - 0x8504, flag - 0x0011, retval - 0x0000
hns3 0000:7d:00.1: Send cmd: 0xe59dc000 0x00000000 0x00000000 0x00000000 0x00000116 0x0000ffff
hns3 0000:7d:00.1: sq record doorbell map failed!
hns3 0000:7d:00.1: Create RC QP failed
Fixes: 0425e3e6e0c7 ("RDMA/hns: Support flush cqe for hip08 in kernel space")
Signed-off-by: Lijun Ou <oulijun@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
io_uring_poll shouldn't signal EPOLLOUT | EPOLLWRNORM if the queue is
full; the old check would always signal EPOLLOUT | EPOLLWRNORM (unless
there were U32_MAX - 1 entries in the SQ queue).
Signed-off-by: Stefan Bühler <source@stbuehler.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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