[ Upstream commit 2d2db7d40254d5fb53b11ebd703cd1ed0c5de7a1 ]
DO NOT access the underlying struct page of an sg table exported
by DMA-buf in dmabuf_imp_to_refs(), this is not allowed.
Please see drivers/dma-buf/dma-buf.c:mangle_sg_table() for details.
Fortunately, here (for special Xen device) we can avoid using
pages and calculate gfns directly from dma addresses provided by
the sg table.
Suggested-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://lore.kernel.org/r/20240107103426.2038075-1-olekstysh@gmail.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit bff2a2d453a1b683378b4508b86b84389f551a00 upstream.
There's a bug that when using the XEN hypervisor with bios with large
multi-page bio vectors on NVMe, the kernel deadlocks [1].
The deadlocks are caused by inability to map a large bio vector -
dma_map_sgtable always returns an error, this gets propagated to the block
layer as BLK_STS_RESOURCE and the block layer retries the request
indefinitely.
XEN uses the swiotlb framework to map discontiguous pages into contiguous
runs that are submitted to the PCIe device. The swiotlb framework has a
limitation on the length of a mapping - this needs to be announced with
the max_mapping_size method to make sure that the hardware drivers do not
create larger mappings.
Without max_mapping_size, the NVMe block driver would create large
mappings that overrun the maximum mapping size.
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Link: https://lore.kernel.org/stable/ZTNH0qtmint%2FzLJZ@mail-itl/ [1]
Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/151bef41-e817-aea9-675-a35fdac4ed@redhat.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 47d970204054f859f35a2237baa75c2d84fcf436 ]
When delaying eoi handling of events, the related elements are queued
into the percpu lateeoi list. In case the list isn't empty, the
elements should be sorted by the time when eoi handling is to happen.
Unfortunately a new element will never be queued at the start of the
list, even if it has a handling time lower than all other list
elements.
Fix that by handling that case the same way as for an empty list.
Fixes: e99502f76271 ("xen/events: defer eoi in case of excessive number of events")
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2c269f42d0f382743ab230308b836ffe5ae9b2ae ]
Linux enables MSI-X before disabling INTx, but keeps MSI-X masked until
the table is filled. Then it disables INTx just before clearing MASKALL
bit. Currently this approach is rejected by xen-pciback.
According to the PCIe spec, device cannot use INTx when MSI/MSI-X is
enabled (in other words: enabling MSI/MSI-X implicitly disables INTx).
Change the logic to consider INTx disabled if MSI/MSI-X is enabled. This
applies to three places:
- checking currently enabled interrupts type,
- transition to MSI/MSI-X - where INTx would be implicitly disabled,
- clearing INTx disable bit - which can be allowed even if MSI/MSI-X is
enabled, as device should consider INTx disabled anyway in that case
Fixes: 5e29500eba2a ("xen-pciback: Allow setting PCI_MSIX_FLAGS_MASKALL too")
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Acked-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20231016131348.1734721-1-marmarek@invisiblethingslab.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
