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When we looked into FIO performance with swiotlb enabled in VM, we found
swiotlb_bounce() is always called one more time than expected for each DMA
read request.
It turns out that the bounce buffer is copied to original DMA buffer twice
after the completion of a DMA request (one is done by in
dma_direct_sync_single_for_cpu(), the other by swiotlb_tbl_unmap_single()).
But the content in bounce buffer actually doesn't change between the two
rounds of copy. So, one round of copy is redundant.
Pass DMA_ATTR_SKIP_CPU_SYNC flag to swiotlb_tbl_unmap_single() to
skip the memory copy in it.
This fix increases FIO 64KB sequential read throughput in a guest with
swiotlb=force by 5.6%.
Fixes: 55897af63091 ("dma-direct: merge swiotlb_dma_ops into the dma_direct code")
Reported-by: Wang Zhaoyang1 <zhaoyang1.wang@intel.com>
Reported-by: Gao Liang <liang.gao@intel.com>
Signed-off-by: Chao Gao <chao.gao@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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pgprot_decrypted is used by AMD SME systems to allow access to memory
that was set to not encrypted using set_memory_decrypted. That only
happens for dma-direct memory as the IOMMU solves the addressing
challenges for the encryption bit using its own remapping.
Move the pgprot_decrypted call out of dma_pgprot which is also used
by the IOMMU mappings and into dma-direct so that it is only used with
memory that was set decrypted.
Fixes: f5ff79fddf0e ("dma-mapping: remove CONFIG_DMA_REMAP")
Reported-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
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Pull dma-mapping updates from Christoph Hellwig:
- do not zero buffer in set_memory_decrypted (Kirill A. Shutemov)
- fix return value of dma-debug __setup handlers (Randy Dunlap)
- swiotlb cleanups (Robin Murphy)
- remove most remaining users of the pci-dma-compat.h API
(Christophe JAILLET)
- share the ABI header for the DMA map_benchmark with userspace
(Tian Tao)
- update the maintainer for DMA MAPPING BENCHMARK (Xiang Chen)
- remove CONFIG_DMA_REMAP (me)
* tag 'dma-mapping-5.18' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: benchmark: extract a common header file for map_benchmark definition
dma-debug: fix return value of __setup handlers
dma-mapping: remove CONFIG_DMA_REMAP
media: v4l2-pci-skeleton: Remove usage of the deprecated "pci-dma-compat.h" API
rapidio/tsi721: Remove usage of the deprecated "pci-dma-compat.h" API
sparc: Remove usage of the deprecated "pci-dma-compat.h" API
agp/intel: Remove usage of the deprecated "pci-dma-compat.h" API
alpha: Remove usage of the deprecated "pci-dma-compat.h" API
MAINTAINERS: update maintainer list of DMA MAPPING BENCHMARK
swiotlb: simplify array allocation
swiotlb: tidy up includes
swiotlb: simplify debugfs setup
swiotlb: do not zero buffer in set_memory_decrypted()
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Halil Pasic points out [1] that the full revert of that commit (revert
in bddac7c1e02b), and that a partial revert that only reverts the
problematic case, but still keeps some of the cleanups is probably
better. 
And that partial revert [2] had already been verified by Oleksandr
Natalenko to also fix the issue, I had just missed that in the long
discussion.
So let's reinstate the cleanups from commit aa6f8dcbab47 ("swiotlb:
rework "fix info leak with DMA_FROM_DEVICE""), and effectively only
revert the part that caused problems.
Link: https://lore.kernel.org/all/20220328013731.017ae3e3.pasic@linux.ibm.com/ [1]
Link: https://lore.kernel.org/all/20220324055732.GB12078@lst.de/ [2]
Link: https://lore.kernel.org/all/4386660.LvFx2qVVIh@natalenko.name/ [3]
Suggested-by: Halil Pasic <pasic@linux.ibm.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Cc: Christoph Hellwig" <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This reverts commit aa6f8dcbab473f3a3c7454b74caa46d36cdc5d13.
It turns out this breaks at least the ath9k wireless driver, and
possibly others.
What the ath9k driver does on packet receive is to set up the DMA
transfer with:
int ath_rx_init(..)
..
bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
common->rx_bufsize,
DMA_FROM_DEVICE);
and then the receive logic (through ath_rx_tasklet()) will fetch
incoming packets
static bool ath_edma_get_buffers(..)
..
dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
common->rx_bufsize, DMA_FROM_DEVICE);
ret = ath9k_hw_process_rxdesc_edma(ah, rs, skb->data);
if (ret == -EINPROGRESS) {
/*let device gain the buffer again*/
dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
common->rx_bufsize, DMA_FROM_DEVICE);
return false;
}
and it's worth noting how that first DMA sync:
dma_sync_single_for_cpu(..DMA_FROM_DEVICE);
is there to make sure the CPU can read the DMA buffer (possibly by
copying it from the bounce buffer area, or by doing some cache flush).
The iommu correctly turns that into a "copy from bounce bufer" so that
the driver can look at the state of the packets.
In the meantime, the device may continue to write to the DMA buffer, but
we at least have a snapshot of the state due to that first DMA sync.
But that _second_ DMA sync:
dma_sync_single_for_device(..DMA_FROM_DEVICE);
is telling the DMA mapping that the CPU wasn't interested in the area
because the packet wasn't there. In the case of a DMA bounce buffer,
that is a no-op.
Note how it's not a sync for the CPU (the "for_device()" part), and it's
not a sync for data written by the CPU (the "DMA_FROM_DEVICE" part).
Or rather, it _should_ be a no-op. That's what commit aa6f8dcbab47
broke: it made the code bounce the buffer unconditionally, and changed
the DMA_FROM_DEVICE to just unconditionally and illogically be
DMA_TO_DEVICE.
[ Side note: purely within the confines of the swiotlb driver it wasn't
entirely illogical: The reason it did that odd DMA_FROM_DEVICE ->
DMA_TO_DEVICE conversion thing is because inside the swiotlb driver,
it uses just a swiotlb_bounce() helper that doesn't care about the
whole distinction of who the sync is for - only which direction to
bounce.
So it took the "sync for device" to mean that the CPU must have been
the one writing, and thought it meant DMA_TO_DEVICE. ]
Also note how the commentary in that commit was wrong, probably due to
that whole confusion, claiming that the commit makes the swiotlb code
"bounce unconditionally (that is, also
when dir == DMA_TO_DEVICE) in order do avoid synchronising back stale
data from the swiotlb buffer"
which is nonsensical for two reasons:
- that "also when dir == DMA_TO_DEVICE" is nonsensical, as that was
exactly when it always did - and should do - the bounce.
- since this is a sync for the device (not for the CPU), we're clearly
fundamentally not coping back stale data from the bounce buffers at
all, because we'd be copying *to* the bounce buffers.
So that commit was just very confused. It confused the direction of the
synchronization (to the device, not the cpu) with the direction of the
DMA (from the device).
Reported-and-bisected-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Reported-by: Olha Cherevyk <olha.cherevyk@gmail.com>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Kalle Valo <kvalo@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Toke Høiland-Jørgensen <toke@toke.dk>
Cc: Maxime Bizon <mbizon@freebox.fr>
Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC updates from Arnd Bergmann:
"SoC specific code is generally used for older platforms that don't
(yet) use device tree to do the same things.
- Support is added for i.MXRT10xx, a Cortex-M7 based microcontroller
from NXP. At the moment this is still incomplete as other portions
are merged through different trees.
- Long abandoned support for running NOMMU ARMv4 or ARMv5 platforms
gets removed, now the Arm NOMMU platforms are limited to the
Cortex-M family of microcontrollers
- Two old PXA boards get removed, along with corresponding driver
bits.
- Continued cleanup of the Intel IXP4xx platforms, removing some
remnants of the old board files.
- Minor Cleanups and fixes for Orion, PXA, MMP, Mstar, Samsung
- CPU idle support for AT91
- A system controller driver for Polarfire"
* tag 'arm-soc-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (29 commits)
ARM: remove support for NOMMU ARMv4/v5
ARM: PXA: fix up decompressor code
soc: microchip: make mpfs_sys_controller_put static
ARM: pxa: remove Intel Imote2 and Stargate 2 boards
ARM: mmp: Fix failure to remove sram device
ARM: mstar: Select ARM_ERRATA_814220
soc: add microchip polarfire soc system controller
ARM: at91: Kconfig: select PM_OPP
ARM: at91: PM: add cpu idle support for sama7g5
ARM: at91: ddr: fix typo to align with datasheet naming
ARM: at91: ddr: align macro definitions
ARM: at91: ddr: remove CONFIG_SOC_SAMA7 dependency
ARM: ixp4xx: Convert to SPARSE_IRQ and P2V
ARM: ixp4xx: Drop all common code
ARM: ixp4xx: Drop custom DMA coherency and bouncing
ARM: ixp4xx: Remove feature bit accessors
net: ixp4xx_hss: Check features using syscon
net: ixp4xx_eth: Drop platform data support
soc: ixp4xx-npe: Access syscon regs using regmap
soc: ixp4xx: Add features from regmap helper
...
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Patch series "mm: enforce pageblock_order < MAX_ORDER".
Having pageblock_order >= MAX_ORDER seems to be able to happen in corner
cases and some parts of the kernel are not prepared for it.
For example, Aneesh has shown [1] that such kernels can be compiled on
ppc64 with 64k base pages by setting FORCE_MAX_ZONEORDER=8, which will
run into a WARN_ON_ONCE(order >= MAX_ORDER) in comapction code right
during boot.
We can get pageblock_order >= MAX_ORDER when the default hugetlb size is
bigger than the maximum allocation granularity of the buddy, in which
case we are no longer talking about huge pages but instead gigantic
pages.
Having pageblock_order >= MAX_ORDER can only make alloc_contig_range()
of such gigantic pages more likely to succeed.
Reliable use of gigantic pages either requires boot time allcoation or
CMA, no need to overcomplicate some places in the kernel to optimize for
corner cases that are broken in other areas of the kernel.
This patch (of 2):
Let's enforce pageblock_order < MAX_ORDER and simplify.
Especially patch #1 can be regarded a cleanup before:
[PATCH v5 0/6] Use pageblock_order for cma and alloc_contig_range
alignment. [2]
[1] https://lkml.kernel.org/r/87r189a2ks.fsf@linux.ibm.com
[2] https://lkml.kernel.org/r/20220211164135.1803616-1-zi.yan@sent.com
Link: https://lkml.kernel.org/r/20220214174132.219303-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Acked-by: Rob Herring <robh@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: John Garry via iommu <iommu@lists.linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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definition
kernel/dma/map_benchmark.c and selftests/dma/dma_map_benchmark.c
have duplicate map_benchmark definitions, which tends to lead to
inconsistent changes to map_benchmark on both sides, extract a
common header file to avoid this problem.
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Acked-by: Barry Song <song.bao.hua@hisilicon.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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Unfortunately, we ended up merging an old version of the patch "fix info
leak with DMA_FROM_DEVICE" instead of merging the latest one. Christoph
(the swiotlb maintainer), he asked me to create an incremental fix
(after I have pointed this out the mix up, and asked him for guidance).
So here we go.
The main differences between what we got and what was agreed are:
* swiotlb_sync_single_for_device is also required to do an extra bounce
* We decided not to introduce DMA_ATTR_OVERWRITE until we have exploiters
* The implantation of DMA_ATTR_OVERWRITE is flawed: DMA_ATTR_OVERWRITE
must take precedence over DMA_ATTR_SKIP_CPU_SYNC
Thus this patch removes DMA_ATTR_OVERWRITE, and makes
swiotlb_sync_single_for_device() bounce unconditionally (that is, also
when dir == DMA_TO_DEVICE) in order do avoid synchronising back stale
data from the swiotlb buffer.
Let me note, that if the size used with dma_sync_* API is less than the
size used with dma_[un]map_*, under certain circumstances we may still
end up with swiotlb not being transparent. In that sense, this is no
perfect fix either.
To get this bullet proof, we would have to bounce the entire
mapping/bounce buffer. For that we would have to figure out the starting
address, and the size of the mapping in
swiotlb_sync_single_for_device(). While this does seem possible, there
seems to be no firm consensus on how things are supposed to work.
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Fixes: ddbd89deb7d3 ("swiotlb: fix info leak with DMA_FROM_DEVICE")
Cc: stable@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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When valid kernel command line parameters
dma_debug=off dma_debug_entries=100
are used, they are reported as Unknown parameters and added to init's
environment strings, polluting it.
Unknown kernel command line parameters "BOOT_IMAGE=/boot/bzImage-517rc5
dma_debug=off dma_debug_entries=100", will be passed to user space.
and
Run /sbin/init as init process
with arguments:
/sbin/init
with environment:
HOME=/
TERM=linux
BOOT_IMAGE=/boot/bzImage-517rc5
dma_debug=off
dma_debug_entries=100
Return 1 from these __setup handlers to indicate that the command line
option has been handled.
Fixes: 59d3daafa1726 ("dma-debug: add kernel command line parameters")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru>
Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: iommu@lists.linux-foundation.org
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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CONFIG_DMA_REMAP is used to build a few helpers around the core
vmalloc code, and to use them in case there is a highmem page in
dma-direct, and to make dma coherent allocations be able to use
non-contiguous pages allocations for DMA allocations in the dma-iommu
layer.
Right now it needs to be explicitly selected by architectures, and
is only done so by architectures that require remapping to deal
with devices that are not DMA coherent. Make it unconditional for
builds with CONFIG_MMU as it is very little extra code, but makes
it much more likely that large DMA allocations succeed on x86.
This fixes hot plugging a NVMe thunderbolt SSD for me, which tries
to allocate a 1MB buffer that is otherwise hard to obtain due to
memory fragmentation on a heavily used laptop.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
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The problem I'm addressing was discovered by the LTP test covering
cve-2018-1000204.
A short description of what happens follows:
1) The test case issues a command code 00 (TEST UNIT READY) via the SG_IO
interface with: dxfer_len == 524288, dxdfer_dir == SG_DXFER_FROM_DEV
and a corresponding dxferp. The peculiar thing about this is that TUR
is not reading from the device.
2) In sg_start_req() the invocation of blk_rq_map_user() effectively
bounces the user-space buffer. As if the device was to transfer into
it. Since commit a45b599ad808 ("scsi: sg: allocate with __GFP_ZERO in
sg_build_indirect()") we make sure this first bounce buffer is
allocated with GFP_ZERO.
3) For the rest of the story we keep ignoring that we have a TUR, so the
device won't touch the buffer we prepare as if the we had a
DMA_FROM_DEVICE type of situation. My setup uses a virtio-scsi device
and the buffer allocated by SG is mapped by the function
virtqueue_add_split() which uses DMA_FROM_DEVICE for the "in" sgs (here
scatter-gather and not scsi generics). This mapping involves bouncing
via the swiotlb (we need swiotlb to do virtio in protected guest like
s390 Secure Execution, or AMD SEV).
4) When the SCSI TUR is done, we first copy back the content of the second
(that is swiotlb) bounce buffer (which most likely contains some
previous IO data), to the first bounce buffer, which contains all
zeros. Then we copy back the content of the first bounce buffer to
the user-space buffer.
5) The test case detects that the buffer, which it zero-initialized,
ain't all zeros and fails.
One can argue that this is an swiotlb problem, because without swiotlb
we leak all zeros, and the swiotlb should be transparent in a sense that
it does not affect the outcome (if all other participants are well
behaved).
Copying the content of the original buffer into the swiotlb buffer is
the only way I can think of to make swiotlb transparent in such
scenarios. So let's do just that if in doubt, but allow the driver
to tell us that the whole mapped buffer is going to be overwritten,
in which case we can preserve the old behavior and avoid the performance
impact of the extra bounce.
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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The new PCI driver does not need any of this stuff, so just
drop it.
Cc: iommu@lists.linux-foundation.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220211223238.648934-12-linus.walleij@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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Prefer kcalloc() to kzalloc(array_size()) for allocating an array.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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SWIOTLB's includes have become a great big mess. Restore some order by
consolidating the random different blocks, sorting alphabetically, and
purging some clearly unnecessary entries - linux/io.h is now included
unconditionally, so need not be duplicated in the restricted DMA pool
case; similarly, linux/io.h subsumes asm/io.h; and by now it's a
mystery why asm/dma.h was ever here at all.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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Debugfs functions are already stubbed out for !CONFIG_DEBUG_FS, so we
can remove most of the #ifdefs, just keeping one to manually optimise
away the initcall when it would do nothing. We can also simplify the
code itself by factoring out the directory creation and realising that
the global io_tlb_default_mem now makes debugfs_dir redundant.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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For larger TDX VM, memset() after set_memory_decrypted() in
swiotlb_update_mem_attributes() takes substantial portion of boot time.
Zeroing doesn't serve any functional purpose. Malicious VMM can mess
with decrypted/shared buffer at any point.
Remove the memset().
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux
Pull hyperv updates from Wei Liu:
- More patches for Hyper-V isolation VM support (Tianyu Lan)
- Bug fixes and clean-up patches from various people
* tag 'hyperv-next-signed-20220114' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
scsi: storvsc: Fix storvsc_queuecommand() memory leak
x86/hyperv: Properly deal with empty cpumasks in hyperv_flush_tlb_multi()
Drivers: hv: vmbus: Initialize request offers message for Isolation VM
scsi: storvsc: Fix unsigned comparison to zero
swiotlb: Add CONFIG_HAS_IOMEM check around swiotlb_mem_remap()
x86/hyperv: Fix definition of hv_ghcb_pg variable
Drivers: hv: Fix definition of hypercall input & output arg variables
net: netvsc: Add Isolation VM support for netvsc driver
scsi: storvsc: Add Isolation VM support for storvsc driver
hyper-v: Enable swiotlb bounce buffer for Isolation VM
x86/hyper-v: Add hyperv Isolation VM check in the cc_platform_has()
swiotlb: Add swiotlb bounce buffer remap function for HV IVM
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Merge misc updates from Andrew Morton:
"146 patches.
Subsystems affected by this patch series: kthread, ia64, scripts,
ntfs, squashfs, ocfs2, vfs, and mm (slab-generic, slab, kmemleak,
dax, kasan, debug, pagecache, gup, shmem, frontswap, memremap,
memcg, selftests, pagemap, dma, vmalloc, memory-failure, hugetlb,
userfaultfd, vmscan, mempolicy, oom-kill, hugetlbfs, migration, thp,
ksm, page-poison, percpu, rmap, zswap, zram, cleanups, hmm, and
damon)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (146 commits)
mm/damon: hide kernel pointer from tracepoint event
mm/damon/vaddr: hide kernel pointer from damon_va_three_regions() failure log
mm/damon/vaddr: use pr_debug() for damon_va_three_regions() failure logging
mm/damon/dbgfs: remove an unnecessary variable
mm/damon: move the implementation of damon_insert_region to damon.h
mm/damon: add access checking for hugetlb pages
Docs/admin-guide/mm/damon/usage: update for schemes statistics
mm/damon/dbgfs: support all DAMOS stats
Docs/admin-guide/mm/damon/reclaim: document statistics parameters
mm/damon/reclaim: provide reclamation statistics
mm/damon/schemes: account how many times quota limit has exceeded
mm/damon/schemes: account scheme actions that successfully applied
mm/damon: remove a mistakenly added comment for a future feature
Docs/admin-guide/mm/damon/usage: update for kdamond_pid and (mk|rm)_contexts
Docs/admin-guide/mm/damon/usage: mention tracepoint at the beginning
Docs/admin-guide/mm/damon/usage: remove redundant information
Docs/admin-guide/mm/damon/usage: update for scheme quotas and watermarks
mm/damon: convert macro functions to static inline functions
mm/damon: modify damon_rand() macro to static inline function
mm/damon: move damon_rand() definition into damon.h
...
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Currently three dma atomic pools are initialized as long as the relevant
kernel codes are built in. While in kdump kernel of x86_64, this is not
right when trying to create atomic_pool_dma, because there's no managed
pages in DMA zone. In the case, DMA zone only has low 1M memory
presented and locked down by memblock allocator. So no pages are added
into buddy of DMA zone. Please check commit f1d4d47c5851 ("x86/setup:
Always reserve the first 1M of RAM").
Then in kdump kernel of x86_64, it always prints below failure message:
DMA: preallocated 128 KiB GFP_KERNEL pool for atomic allocations
swapper/0: page allocation failure: order:5, mode:0xcc1(GFP_KERNEL|GFP_DMA), nodemask=(null),cpuset=/,mems_allowed=0
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-0.rc5.20210611git929d931f2b40.42.fc35.x86_64 #1
Hardware name: Dell Inc. PowerEdge R910/0P658H, BIOS 2.12.0 06/04/2018
Call Trace:
dump_stack+0x7f/0xa1
warn_alloc.cold+0x72/0xd6
__alloc_pages_slowpath.constprop.0+0xf29/0xf50
__alloc_pages+0x24d/0x2c0
alloc_page_interleave+0x13/0xb0
atomic_pool_expand+0x118/0x210
__dma_atomic_pool_init+0x45/0x93
dma_atomic_pool_init+0xdb/0x176
do_one_initcall+0x67/0x320
kernel_init_freeable+0x290/0x2dc
kernel_init+0xa/0x111
ret_from_fork+0x22/0x30
Mem-Info:
......
DMA: failed to allocate 128 KiB GFP_KERNEL|GFP_DMA pool for atomic allocation
DMA: preallocated 128 KiB GFP_KERNEL|GFP_DMA32 pool for atomic allocations
Here, let's check if DMA zone has managed pages, then create
atomic_pool_dma if yes. Otherwise just skip it.
Link: https://lkml.kernel.org/r/20211223094435.248523-3-bhe@redhat.com
Fixes: 6f599d84231f ("x86/kdump: Always reserve the low 1M when the crashkernel option is specified")
Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: John Donnelly <john.p.donnelly@oracle.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: David Rientjes <rientjes@google.com>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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HAS_IOMEM option may not be selected on some platforms (e.g, s390) and
this will cause compilation failure due to missing memremap()
implementation.
Fix it by stubbing out swiotlb_mem_remap when CONFIG_HAS_IOMEM is not
set.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
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In Isolation VM with AMD SEV, bounce buffer needs to be accessed via
extra address space which is above shared_gpa_boundary (E.G 39 bit
address line) reported by Hyper-V CPUID ISOLATION_CONFIG. The access
physical address will be original physical address + shared_gpa_boundary.
The shared_gpa_boundary in the AMD SEV SNP spec is called virtual top of
memory(vTOM). Memory addresses below vTOM are automatically treated as
private while memory above vTOM is treated as shared.
Expose swiotlb_unencrypted_base for platforms to set unencrypted
memory base offset and platform calls swiotlb_update_mem_attributes()
to remap swiotlb mem to unencrypted address space. memremap() can
not be called in the early stage and so put remapping code into
swiotlb_update_mem_attributes(). Store remap address and use it to copy
data from/to swiotlb bounce buffer.
Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20211213071407.314309-2-ltykernel@gmail.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
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Add a helper to check if a potentially blocking operation should
dip into the atomic pools.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
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Add a new helper to deal with the swiotlb case. This keeps the code
nicely boundled and removes the not required call to
dma_direct_optimal_gfp_mask for the swiotlb case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
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swiotlb_alloc and swiotlb_free are properly stubbed out if
CONFIG_DMA_RESTRICTED_POOL is not set, so skip the extra checks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
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Instead of blindly running into a blocking operation for a non-blocking gfp,
return NULL and spew an error. Note that Kconfig prevents this for all
currently relevant platforms, and this is just a debug check.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
|
|
If the architecture can't remap or set an address uncached there is no way
to fullfill a request for a coherent allocation. Return NULL in that case.
Note that this case currently does not happen, so this is a theoretical
fixup and/or a preparation for eventually supporting platforms that
can't support coherent allocations with the generic code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
|
|
Add a big central !dev_is_dma_coherent(dev) block to deal with as much
as of the uncached allocation schemes and document the schemes a bit
better.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
|
|
Split the code for DMA_ATTR_NO_KERNEL_MAPPING allocations into a separate
helper to make dma_direct_alloc a little more readable.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: David Rientjes <rientjes@google.com>
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Add two local variables to track if we want to remap the returned
address using vmap or call dma_set_uncached and use that to simplify
the code flow.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
|
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We must never let unencrypted memory go back into the general page pool.
So if we fail to set it back to encrypted when freeing DMA memory, leak
the memory instead and warn the user.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
|
|
Remapped allocations handle the encrypted bit through the pgprot passed
to vmap, so there is no call dma_set_decrypted. Note that this case is
currently entirely theoretical as no valid kernel configuration supports
remapped allocations and memory encryption currently.
Signed-off-by: Christoph Hellwig <hch@lst.de>
|
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Factor out helpers the make dealing with memory encryption a little less
cumbersome.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
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|
Pull dma-mapping updates from Christoph Hellwig:
"Just a small set of changes this time. The request dma_direct_alloc
cleanups are still under review and haven't made the cut.
Summary:
- convert sparc32 to the generic dma-direct code
- use bitmap_zalloc (Christophe JAILLET)"
* tag 'dma-mapping-5.16' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: use 'bitmap_zalloc()' when applicable
sparc32: use DMA_DIRECT_REMAP
sparc32: remove dma_make_coherent
sparc32: remove the call to dma_make_coherent in arch_dma_free
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Merge misc updates from Andrew Morton:
"257 patches.
Subsystems affected by this patch series: scripts, ocfs2, vfs, and
mm (slab-generic, slab, slub, kconfig, dax, kasan, debug, pagecache,
gup, swap, memcg, pagemap, mprotect, mremap, iomap, tracing, vmalloc,
pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, tools,
memblock, oom-kill, hugetlbfs, migration, thp, readahead, nommu, ksm,
vmstat, madvise, memory-hotplug, rmap, zsmalloc, highmem, zram,
cleanups, kfence, and damon)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (257 commits)
mm/damon: remove return value from before_terminate callback
mm/damon: fix a few spelling mistakes in comments and a pr_debug message
mm/damon: simplify stop mechanism
Docs/admin-guide/mm/pagemap: wordsmith page flags descriptions
Docs/admin-guide/mm/damon/start: simplify the content
Docs/admin-guide/mm/damon/start: fix a wrong link
Docs/admin-guide/mm/damon/start: fix wrong example commands
mm/damon/dbgfs: add adaptive_targets list check before enable monitor_on
mm/damon: remove unnecessary variable initialization
Documentation/admin-guide/mm/damon: add a document for DAMON_RECLAIM
mm/damon: introduce DAMON-based Reclamation (DAMON_RECLAIM)
selftests/damon: support watermarks
mm/damon/dbgfs: support watermarks
mm/damon/schemes: activate schemes based on a watermarks mechanism
tools/selftests/damon: update for regions prioritization of schemes
mm/damon/dbgfs: support prioritization weights
mm/damon/vaddr,paddr: support pageout prioritization
mm/damon/schemes: prioritize regions within the quotas
mm/damon/selftests: support schemes quotas
mm/damon/dbgfs: support quotas of schemes
...
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Rename memblock_free_ptr() to memblock_free() and use memblock_free()
when freeing a virtual pointer so that memblock_free() will be a
counterpart of memblock_alloc()
The callers are updated with the below semantic patch and manual
addition of (void *) casting to pointers that are represented by
unsigned long variables.
@@
identifier vaddr;
expression size;
@@
(
- memblock_phys_free(__pa(vaddr), size);
+ memblock_free(vaddr, size);
|
- memblock_free_ptr(vaddr, size);
+ memblock_free(vaddr, size);
)
[sfr@canb.auug.org.au: fixup]
Link: https://lkml.kernel.org/r/20211018192940.3d1d532f@canb.auug.org.au
Link: https://lkml.kernel.org/r/20210930185031.18648-7-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Juergen Gross <jgross@suse.com>
Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Since memblock_free() operates on a physical range, make its name
reflect it and rename it to memblock_phys_free(), so it will be a
logical counterpart to memblock_phys_alloc().
The callers are updated with the below semantic patch:
@@
expression addr;
expression size;
@@
- memblock_free(addr, size);
+ memblock_phys_free(addr, size);
Link: https://lkml.kernel.org/r/20210930185031.18648-6-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Juergen Gross <jgross@suse.com>
Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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memblock_free_early_nid() is unused and memblock_free_early() is an
alias for memblock_free().
Replace calls to memblock_free_early() with calls to memblock_free() and
remove memblock_free_early() and memblock_free_early_nid().
Link: https://lkml.kernel.org/r/20210930185031.18648-4-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Juergen Gross <jgross@suse.com>
Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull iommu updates from Joerg Roedel:
- Intel IOMMU Updates fro Lu Baolu:
- Dump DMAR translation structure when DMA fault occurs
- An optimization in the page table manipulation code
- Use second level for GPA->HPA translation
- Various cleanups
- Arm SMMU Updates from Will
- Minor optimisations to SMMUv3 command creation and submission
- Numerous new compatible string for Qualcomm SMMUv2 implementations
- Fixes for the SWIOTLB based implemenation of dma-iommu code for
untrusted devices
- Add support for r8a779a0 to the Renesas IOMMU driver and DT matching
code for r8a77980
- A couple of cleanups and fixes for the Apple DART IOMMU driver
- Make use of generic report_iommu_fault() interface in the AMD IOMMU
driver
- Various smaller fixes and cleanups
* tag 'iommu-updates-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (35 commits)
iommu/dma: Fix incorrect error return on iommu deferred attach
iommu/dart: Initialize DART_STREAMS_ENABLE
iommu/dma: Use kvcalloc() instead of kvzalloc()
iommu/tegra-smmu: Use devm_bitmap_zalloc when applicable
iommu/dart: Use kmemdup instead of kzalloc and memcpy
iommu/vt-d: Avoid duplicate removing in __domain_mapping()
iommu/vt-d: Convert the return type of first_pte_in_page to bool
iommu/vt-d: Clean up unused PASID updating functions
iommu/vt-d: Delete dev_has_feat callback
iommu/vt-d: Use second level for GPA->HPA translation
iommu/vt-d: Check FL and SL capability sanity in scalable mode
iommu/vt-d: Remove duplicate identity domain flag
iommu/vt-d: Dump DMAR translation structure when DMA fault occurs
iommu/vt-d: Do not falsely log intel_iommu is unsupported kernel option
iommu/arm-smmu-qcom: Request direct mapping for modem device
iommu: arm-smmu-qcom: Add compatible for QCM2290
dt-bindings: arm-smmu: Add compatible for QCM2290 SoC
iommu/arm-smmu-qcom: Add SM6350 SMMU compatible
dt-bindings: arm-smmu: Add compatible for SM6350 SoC
iommu/arm-smmu-v3: Properly handle the return value of arm_smmu_cmdq_build_cmd()
...
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git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"There's the usual summary below, but the highlights are support for
the Armv8.6 timer extensions, KASAN support for asymmetric MTE, the
ability to kexec() with the MMU enabled and a second attempt at
switching to the generic pfn_valid() implementation.
Summary:
- Support for the Arm8.6 timer extensions, including a
self-synchronising view of the system registers to elide some
expensive ISB instructions.
- Exception table cleanup and rework so that the fixup handlers
appear correctly in backtraces.
- A handful of miscellaneous changes, the main one being selection of
CONFIG_HAVE_POSIX_CPU_TIMERS_TASK_WORK.
- More mm and pgtable cleanups.
- KASAN support for "asymmetric" MTE, where tag faults are reported
synchronously for loads (via an exception) and asynchronously for
stores (via a register).
- Support for leaving the MMU enabled during kexec relocation, which
significantly speeds up the operation.
- Minor improvements to our perf PMU drivers.
- Improvements to the compat vDSO build system, particularly when
building with LLVM=1.
- Preparatory work for handling some Coresight TRBE tracing errata.
- Cleanup and refactoring of the SVE code to pave the way for SME
support in future.
- Ensure SCS pages are unpoisoned immediately prior to freeing them
when KASAN is enabled for the vmalloc area.
- Try moving to the generic pfn_valid() implementation again now that
the DMA mapping issue from last time has been resolved.
- Numerous improvements and additions to our FPSIMD and SVE
selftests"
[ armv8.6 timer updates were in a shared branch and already came in
through -tip in the timer pull - Linus ]
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (85 commits)
arm64: Select POSIX_CPU_TIMERS_TASK_WORK
arm64: Document boot requirements for FEAT_SME_FA64
arm64/sve: Fix warnings when SVE is disabled
arm64/sve: Add stub for sve_max_virtualisable_vl()
arm64: errata: Add detection for TRBE write to out-of-range
arm64: errata: Add workaround for TSB flush failures
arm64: errata: Add detection for TRBE overwrite in FILL mode
arm64: Add Neoverse-N2, Cortex-A710 CPU part definition
selftests: arm64: Factor out utility functions for assembly FP tests
arm64: vmlinux.lds.S: remove `.fixup` section
arm64: extable: add load_unaligned_zeropad() handler
arm64: extable: add a dedicated uaccess handler
arm64: extable: add `type` and `data` fields
arm64: extable: use `ex` for `exception_table_entry`
arm64: extable: make fixup_exception() return bool
arm64: extable: consolidate definitions
arm64: gpr-num: support W registers
arm64: factor out GPR numbering helpers
arm64: kvm: use kvm_exception_table_entry
arm64: lib: __arch_copy_to_user(): fold fixups into body
...
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull generic confidential computing updates from Borislav Petkov:
"Add an interface called cc_platform_has() which is supposed to be used
by confidential computing solutions to query different aspects of the
system.
The intent behind it is to unify testing of such aspects instead of
having each confidential computing solution add its own set of tests
to code paths in the kernel, leading to an unwieldy mess"
* tag 'x86_cc_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
treewide: Replace the use of mem_encrypt_active() with cc_platform_has()
x86/sev: Replace occurrences of sev_es_active() with cc_platform_has()
x86/sev: Replace occurrences of sev_active() with cc_platform_has()
x86/sme: Replace occurrences of sme_active() with cc_platform_has()
powerpc/pseries/svm: Add a powerpc version of cc_platform_has()
x86/sev: Add an x86 version of cc_platform_has()
arch/cc: Introduce a function to check for confidential computing features
x86/ioremap: Selectively build arch override encryption functions
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'arm/tegra', 'iommu/fixes', 'x86/amd', 'x86/vt-d' and 'core' into next
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'dma_mem->bitmap' is a bitmap. So use 'bitmap_zalloc()' to simplify code,
improve the semantic and avoid some open-coded arithmetic in allocator
arguments.
Also change the corresponding 'kfree()' into 'bitmap_free()' to keep
consistency.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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Pull dma-mapping fixes from Christoph Hellwig:
- fix more dma-debug fallout (Gerald Schaefer, Hamza Mahfooz)
- fix a kerneldoc warning (Logan Gunthorpe)
* tag 'dma-mapping-5.15-2' of git://git.infradead.org/users/hch/dma-mapping:
dma-debug: teach add_dma_entry() about DMA_ATTR_SKIP_CPU_SYNC
dma-debug: fix sg checks in debug_dma_map_sg()
dma-mapping: fix the kerneldoc for dma_map_sgtable()
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Mapping something twice should be possible as long as,
DMA_ATTR_SKIP_CPU_SYNC is passed to the strictly speaking second relevant
mapping operation (that attempts to map the same thing). So, don't issue a
warning if the specified condition is met in add_dma_entry().
Signed-off-by: Hamza Mahfooz <someguy@effective-light.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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The following warning occurred sporadically on s390:
DMA-API: nvme 0006:00:00.0: device driver maps memory from kernel text or rodata [addr=0000000048cc5e2f] [len=131072]
WARNING: CPU: 4 PID: 825 at kernel/dma/debug.c:1083 check_for_illegal_area+0xa8/0x138
It is a false-positive warning, due to broken logic in debug_dma_map_sg().
check_for_illegal_area() checks for overlay of sg elements with kernel text
or rodata. It is called with sg_dma_len(s) instead of s->length as
parameter. After the call to ->map_sg(), sg_dma_len() will contain the
length of possibly combined sg elements in the DMA address space, and not
the individual sg element length, which would be s->length.
The check will then use the physical start address of an sg element, and
add the DMA length for the overlap check, which could result in the false
warning, because the DMA length can be larger than the actual single sg
element length.
In addition, the call to check_for_illegal_area() happens in the iteration
over mapped_ents, which will not include all individual sg elements if
any of them were combined in ->map_sg().
Fix this by using s->length instead of sg_dma_len(s). Also put the call to
check_for_illegal_area() in a separate loop, iterating over all the
individual sg elements ("nents" instead of "mapped_ents").
While at it, as suggested by Robin Murphy, also move check_for_stack()
inside the new loop, as it is similarly concerned with validating the
individual sg elements.
Link: https://lore.kernel.org/lkml/20210705185252.4074653-1-gerald.schaefer@linux.ibm.com
Fixes: 884d05970bfb ("dma-debug: use sg_dma_len accessor")
Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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htmldocs began producing the following warnings:
kernel/dma/mapping.c:256: WARNING: Definition list ends without a
blank line; unexpected unindent.
kernel/dma/mapping.c:257: WARNING: Bullet list ends without a blank
line; unexpected unindent.
Reformatting the list without hyphens fixes the warnings and produces
both a readable text and HTML output.
Fixes: fffe3cc8c219 ("dma-mapping: allow map_sg() ops to return negative error code")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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Replace uses of mem_encrypt_active() with calls to cc_platform_has() with
the CC_ATTR_MEM_ENCRYPT attribute.
Remove the implementation of mem_encrypt_active() across all arches.
For s390, since the default implementation of the cc_platform_has()
matches the s390 implementation of mem_encrypt_active(), cc_platform_has()
does not need to be implemented in s390 (the config option
ARCH_HAS_CC_PLATFORM is not set).
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210928191009.32551-9-bp@alien8.de
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dma_map_resource() uses pfn_valid() to ensure the range is not RAM.
However, pfn_valid() only checks for availability of the memory map for a
PFN but it does not ensure that the PFN is actually backed by RAM.
As dma_map_resource() is the only method in DMA mapping APIs that has this
check, simply drop the pfn_valid() test from dma_map_resource().
Link: https://lore.kernel.org/all/20210824173741.GC623@arm.com/
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210930013039.11260-2-rppt@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
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Add an argument to swiotlb_tbl_map_single that specifies the desired
alignment of the allocated buffer. This is used by dma-iommu to ensure
the buffer is aligned to the iova granule size when using swiotlb with
untrusted sub-granule mappings. This addresses an issue where adjacent
slots could be exposed to the untrusted device if IO_TLB_SIZE < iova
granule < PAGE_SIZE.
Signed-off-by: David Stevens <stevensd@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210929023300.335969-7-stevensd@google.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
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