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2021-09-22vfio: Use config not menuconfig for VFIO_NOIOMMUJason Gunthorpe
[ Upstream commit 26c22cfde5dd6e63f25c48458b0185dcb0fbb2fd ] VFIO_NOIOMMU is supposed to be an element in the VFIO menu, not start a new menu. Correct this copy-paste mistake. Fixes: 03a76b60f8ba ("vfio: Include No-IOMMU mode") Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Link: https://lore.kernel.org/r/0-v1-3f0b685c3679+478-vfio_menuconfig_jgg@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20vfio/pci: Handle concurrent vma faultsAlex Williamson
[ Upstream commit 6a45ece4c9af473555f01f0f8b97eba56e3c7d0d ] io_remap_pfn_range() will trigger a BUG_ON if it encounters a populated pte within the mapping range. This can occur because we map the entire vma on fault and multiple faults can be blocked behind the vma_lock. This leads to traces like the one reported below. We can use our vma_list to test whether a given vma is mapped to avoid this issue. [ 1591.733256] kernel BUG at mm/memory.c:2177! [ 1591.739515] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP [ 1591.747381] Modules linked in: vfio_iommu_type1 vfio_pci vfio_virqfd vfio pv680_mii(O) [ 1591.760536] CPU: 2 PID: 227 Comm: lcore-worker-2 Tainted: G O 5.11.0-rc3+ #1 [ 1591.770735] Hardware name: , BIOS HixxxxFPGA 1P B600 V121-1 [ 1591.778872] pstate: 40400009 (nZcv daif +PAN -UAO -TCO BTYPE=--) [ 1591.786134] pc : remap_pfn_range+0x214/0x340 [ 1591.793564] lr : remap_pfn_range+0x1b8/0x340 [ 1591.799117] sp : ffff80001068bbd0 [ 1591.803476] x29: ffff80001068bbd0 x28: 0000042eff6f0000 [ 1591.810404] x27: 0000001100910000 x26: 0000001300910000 [ 1591.817457] x25: 0068000000000fd3 x24: ffffa92f1338e358 [ 1591.825144] x23: 0000001140000000 x22: 0000000000000041 [ 1591.832506] x21: 0000001300910000 x20: ffffa92f141a4000 [ 1591.839520] x19: 0000001100a00000 x18: 0000000000000000 [ 1591.846108] x17: 0000000000000000 x16: ffffa92f11844540 [ 1591.853570] x15: 0000000000000000 x14: 0000000000000000 [ 1591.860768] x13: fffffc0000000000 x12: 0000000000000880 [ 1591.868053] x11: ffff0821bf3d01d0 x10: ffff5ef2abd89000 [ 1591.875932] x9 : ffffa92f12ab0064 x8 : ffffa92f136471c0 [ 1591.883208] x7 : 0000001140910000 x6 : 0000000200000000 [ 1591.890177] x5 : 0000000000000001 x4 : 0000000000000001 [ 1591.896656] x3 : 0000000000000000 x2 : 0168044000000fd3 [ 1591.903215] x1 : ffff082126261880 x0 : fffffc2084989868 [ 1591.910234] Call trace: [ 1591.914837] remap_pfn_range+0x214/0x340 [ 1591.921765] vfio_pci_mmap_fault+0xac/0x130 [vfio_pci] [ 1591.931200] __do_fault+0x44/0x12c [ 1591.937031] handle_mm_fault+0xcc8/0x1230 [ 1591.942475] do_page_fault+0x16c/0x484 [ 1591.948635] do_translation_fault+0xbc/0xd8 [ 1591.954171] do_mem_abort+0x4c/0xc0 [ 1591.960316] el0_da+0x40/0x80 [ 1591.965585] el0_sync_handler+0x168/0x1b0 [ 1591.971608] el0_sync+0x174/0x180 [ 1591.978312] Code: eb1b027f 540000c0 f9400022 b4fffe02 (d4210000) Fixes: 11c4cd07ba11 ("vfio-pci: Fault mmaps to enable vma tracking") Reported-by: Zeng Tao <prime.zeng@hisilicon.com> Suggested-by: Zeng Tao <prime.zeng@hisilicon.com> Link: https://lore.kernel.org/r/162497742783.3883260.3282953006487785034.stgit@omen Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-10vfio/platform: fix module_put call in error flowMax Gurtovoy
[ Upstream commit dc51ff91cf2d1e9a2d941da483602f71d4a51472 ] The ->parent_module is the one that use in try_module_get. It should also be the one the we use in module_put during vfio_platform_open(). Fixes: 32a2d71c4e80 ("vfio: platform: introduce vfio-platform-base module") Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com> Message-Id: <20210518192133.59195-1-mgurtovoy@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-10vfio/pci: zap_vma_ptes() needs MMURandy Dunlap
[ Upstream commit 2a55ca37350171d9b43d561528f23d4130097255 ] zap_vma_ptes() is only available when CONFIG_MMU is set/enabled. Without CONFIG_MMU, vfio_pci.o has build errors, so make VFIO_PCI depend on MMU. riscv64-linux-ld: drivers/vfio/pci/vfio_pci.o: in function `vfio_pci_mmap_open': vfio_pci.c:(.text+0x1ec): undefined reference to `zap_vma_ptes' riscv64-linux-ld: drivers/vfio/pci/vfio_pci.o: in function `.L0 ': vfio_pci.c:(.text+0x165c): undefined reference to `zap_vma_ptes' Fixes: 11c4cd07ba11 ("vfio-pci: Fault mmaps to enable vma tracking") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: kernel test robot <lkp@intel.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Cornelia Huck <cohuck@redhat.com> Cc: kvm@vger.kernel.org Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Eric Auger <eric.auger@redhat.com> Message-Id: <20210515190856.2130-1-rdunlap@infradead.org> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-10vfio/pci: Fix error return code in vfio_ecap_init()Zhen Lei
[ Upstream commit d1ce2c79156d3baf0830990ab06d296477b93c26 ] The error code returned from vfio_ext_cap_len() is stored in 'len', not in 'ret'. Fixes: 89e1f7d4c66d ("vfio: Add PCI device driver") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com> Message-Id: <20210515020458.6771-1-thunder.leizhen@huawei.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-22vfio/mdev: Do not allow a mdev_type to have a NULL parent pointerJason Gunthorpe
[ Upstream commit b5a1f8921d5040bb788492bf33a66758021e4be5 ] There is a small race where the parent is NULL even though the kobj has already been made visible in sysfs. For instance the attribute_group is made visible in sysfs_create_files() and the mdev_type_attr_show() does: ret = attr->show(kobj, type->parent->dev, buf); Which will crash on NULL parent. Move the parent setup to before the type pointer leaves the stack frame. Fixes: 7b96953bc640 ("vfio: Mediated device Core driver") Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Message-Id: <2-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-06vfio/pci: Move dummy_resources_list init in vfio_pci_probe()Eric Auger
[ Upstream commit 16b8fe4caf499ae8e12d2ab1b1324497e36a7b83 ] In case an error occurs in vfio_pci_enable() before the call to vfio_pci_probe_mmaps(), vfio_pci_disable() will try to iterate on an uninitialized list and cause a kernel panic. Lets move to the initialization to vfio_pci_probe() to fix the issue. Signed-off-by: Eric Auger <eric.auger@redhat.com> Fixes: 05f0c03fbac1 ("vfio-pci: Allow to mmap sub-page MMIO BARs if the mmio page is exclusive") CC: Stable <stable@vger.kernel.org> # v4.7+ Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30vfio-pci: Use io_remap_pfn_range() for PCI IO memoryJason Gunthorpe
[ Upstream commit 7b06a56d468b756ad6bb43ac21b11e474ebc54a0 ] commit f8f6ae5d077a ("mm: always have io_remap_pfn_range() set pgprot_decrypted()") allows drivers using mmap to put PCI memory mapped BAR space into userspace to work correctly on AMD SME systems that default to all memory encrypted. Since vfio_pci_mmap_fault() is working with PCI memory mapped BAR space it should be calling io_remap_pfn_range() otherwise it will not work on SME systems. Fixes: 11c4cd07ba11 ("vfio-pci: Fault mmaps to enable vma tracking") Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: Peter Xu <peterx@redhat.com> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-18vfio: platform: fix reference leak in vfio_platform_openZhang Qilong
[ Upstream commit bb742ad01961a3b9d1f9d19375487b879668b6b2 ] pm_runtime_get_sync() will increment pm usage counter even it failed. Forgetting to call pm_runtime_put will result in reference leak in vfio_platform_open, so we should fix it. Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com> Acked-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-30vfio iommu type1: Fix memory leak in vfio_iommu_type1_pin_pagesXiaoyang Xu
[ Upstream commit 2e6cfd496f5b57034cf2aec738799571b5a52124 ] pfn is not added to pfn_list when vfio_add_to_pfn_list fails. vfio_unpin_page_external will exit directly without calling vfio_iova_put_vfio_pfn. This will lead to a memory leak. Fixes: a54eb55045ae ("vfio iommu type1: Add support for mediated devices") Signed-off-by: Xiaoyang Xu <xuxiaoyang2@huawei.com> [aw: simplified logic, add Fixes] Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-30vfio/pci: Clear token on bypass registration failureAlex Williamson
[ Upstream commit 852b1beecb6ff9326f7ca4bc0fe69ae860ebdb9e ] The eventfd context is used as our irqbypass token, therefore if an eventfd is re-used, our token is the same. The irqbypass code will return an -EBUSY in this case, but we'll still attempt to unregister the producer, where if that duplicate token still exists, results in removing the wrong object. Clear the token of failed producers so that they harmlessly fall out when unregistered. Fixes: 6d7425f109d2 ("vfio: Register/unregister irq_bypass_producer") Reported-by: guomin chen <guomin_chen@sina.com> Tested-by: guomin chen <guomin_chen@sina.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01vfio/pci: fix racy on error and request eventfd ctxZeng Tao
[ Upstream commit b872d0640840018669032b20b6375a478ed1f923 ] The vfio_pci_release call will free and clear the error and request eventfd ctx while these ctx could be in use at the same time in the function like vfio_pci_request, and it's expected to protect them under the vdev->igate mutex, which is missing in vfio_pci_release. This issue is introduced since commit 1518ac272e78 ("vfio/pci: fix memory leaks of eventfd ctx"),and since commit 5c5866c593bb ("vfio/pci: Clear error and request eventfd ctx after releasing"), it's very easily to trigger the kernel panic like this: [ 9513.904346] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 [ 9513.913091] Mem abort info: [ 9513.915871] ESR = 0x96000006 [ 9513.918912] EC = 0x25: DABT (current EL), IL = 32 bits [ 9513.924198] SET = 0, FnV = 0 [ 9513.927238] EA = 0, S1PTW = 0 [ 9513.930364] Data abort info: [ 9513.933231] ISV = 0, ISS = 0x00000006 [ 9513.937048] CM = 0, WnR = 0 [ 9513.940003] user pgtable: 4k pages, 48-bit VAs, pgdp=0000007ec7d12000 [ 9513.946414] [0000000000000008] pgd=0000007ec7d13003, p4d=0000007ec7d13003, pud=0000007ec728c003, pmd=0000000000000000 [ 9513.956975] Internal error: Oops: 96000006 [#1] PREEMPT SMP [ 9513.962521] Modules linked in: vfio_pci vfio_virqfd vfio_iommu_type1 vfio hclge hns3 hnae3 [last unloaded: vfio_pci] [ 9513.972998] CPU: 4 PID: 1327 Comm: bash Tainted: G W 5.8.0-rc4+ #3 [ 9513.980443] Hardware name: Huawei TaiShan 2280 V2/BC82AMDC, BIOS 2280-V2 CS V3.B270.01 05/08/2020 [ 9513.989274] pstate: 80400089 (Nzcv daIf +PAN -UAO BTYPE=--) [ 9513.994827] pc : _raw_spin_lock_irqsave+0x48/0x88 [ 9513.999515] lr : eventfd_signal+0x6c/0x1b0 [ 9514.003591] sp : ffff800038a0b960 [ 9514.006889] x29: ffff800038a0b960 x28: ffff007ef7f4da10 [ 9514.012175] x27: ffff207eefbbfc80 x26: ffffbb7903457000 [ 9514.017462] x25: ffffbb7912191000 x24: ffff007ef7f4d400 [ 9514.022747] x23: ffff20be6e0e4c00 x22: 0000000000000008 [ 9514.028033] x21: 0000000000000000 x20: 0000000000000000 [ 9514.033321] x19: 0000000000000008 x18: 0000000000000000 [ 9514.038606] x17: 0000000000000000 x16: ffffbb7910029328 [ 9514.043893] x15: 0000000000000000 x14: 0000000000000001 [ 9514.049179] x13: 0000000000000000 x12: 0000000000000002 [ 9514.054466] x11: 0000000000000000 x10: 0000000000000a00 [ 9514.059752] x9 : ffff800038a0b840 x8 : ffff007ef7f4de60 [ 9514.065038] x7 : ffff007fffc96690 x6 : fffffe01faffb748 [ 9514.070324] x5 : 0000000000000000 x4 : 0000000000000000 [ 9514.075609] x3 : 0000000000000000 x2 : 0000000000000001 [ 9514.080895] x1 : ffff007ef7f4d400 x0 : 0000000000000000 [ 9514.086181] Call trace: [ 9514.088618] _raw_spin_lock_irqsave+0x48/0x88 [ 9514.092954] eventfd_signal+0x6c/0x1b0 [ 9514.096691] vfio_pci_request+0x84/0xd0 [vfio_pci] [ 9514.101464] vfio_del_group_dev+0x150/0x290 [vfio] [ 9514.106234] vfio_pci_remove+0x30/0x128 [vfio_pci] [ 9514.111007] pci_device_remove+0x48/0x108 [ 9514.115001] device_release_driver_internal+0x100/0x1b8 [ 9514.120200] device_release_driver+0x28/0x38 [ 9514.124452] pci_stop_bus_device+0x68/0xa8 [ 9514.128528] pci_stop_and_remove_bus_device+0x20/0x38 [ 9514.133557] pci_iov_remove_virtfn+0xb4/0x128 [ 9514.137893] sriov_disable+0x3c/0x108 [ 9514.141538] pci_disable_sriov+0x28/0x38 [ 9514.145445] hns3_pci_sriov_configure+0x48/0xb8 [hns3] [ 9514.150558] sriov_numvfs_store+0x110/0x198 [ 9514.154724] dev_attr_store+0x44/0x60 [ 9514.158373] sysfs_kf_write+0x5c/0x78 [ 9514.162018] kernfs_fop_write+0x104/0x210 [ 9514.166010] __vfs_write+0x48/0x90 [ 9514.169395] vfs_write+0xbc/0x1c0 [ 9514.172694] ksys_write+0x74/0x100 [ 9514.176079] __arm64_sys_write+0x24/0x30 [ 9514.179987] el0_svc_common.constprop.4+0x110/0x200 [ 9514.184842] do_el0_svc+0x34/0x98 [ 9514.188144] el0_svc+0x14/0x40 [ 9514.191185] el0_sync_handler+0xb0/0x2d0 [ 9514.195088] el0_sync+0x140/0x180 [ 9514.198389] Code: b9001020 d2800000 52800022 f9800271 (885ffe61) [ 9514.204455] ---[ end trace 648de00c8406465f ]--- [ 9514.212308] note: bash[1327] exited with preempt_count 1 Cc: Qian Cai <cai@lca.pw> Cc: Alex Williamson <alex.williamson@redhat.com> Fixes: 1518ac272e78 ("vfio/pci: fix memory leaks of eventfd ctx") Signed-off-by: Zeng Tao <prime.zeng@hisilicon.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01vfio/pci: Clear error and request eventfd ctx after releasingAlex Williamson
[ Upstream commit 5c5866c593bbd444d0339ede6a8fb5f14ff66d72 ] The next use of the device will generate an underflow from the stale reference. Cc: Qian Cai <cai@lca.pw> Fixes: 1518ac272e78 ("vfio/pci: fix memory leaks of eventfd ctx") Reported-by: Daniel Wagner <dwagner@suse.de> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Tested-by: Daniel Wagner <dwagner@suse.de> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01vfio/pci: fix memory leaks of eventfd ctxQian Cai
[ Upstream commit 1518ac272e789cae8c555d69951b032a275b7602 ] Finished a qemu-kvm (-device vfio-pci,host=0001:01:00.0) triggers a few memory leaks after a while because vfio_pci_set_ctx_trigger_single() calls eventfd_ctx_fdget() without the matching eventfd_ctx_put() later. Fix it by calling eventfd_ctx_put() for those memory in vfio_pci_release() before vfio_device_release(). unreferenced object 0xebff008981cc2b00 (size 128): comm "qemu-kvm", pid 4043, jiffies 4294994816 (age 9796.310s) hex dump (first 32 bytes): 01 00 00 00 6b 6b 6b 6b 00 00 00 00 ad 4e ad de ....kkkk.....N.. ff ff ff ff 6b 6b 6b 6b ff ff ff ff ff ff ff ff ....kkkk........ backtrace: [<00000000917e8f8d>] slab_post_alloc_hook+0x74/0x9c [<00000000df0f2aa2>] kmem_cache_alloc_trace+0x2b4/0x3d4 [<000000005fcec025>] do_eventfd+0x54/0x1ac [<0000000082791a69>] __arm64_sys_eventfd2+0x34/0x44 [<00000000b819758c>] do_el0_svc+0x128/0x1dc [<00000000b244e810>] el0_sync_handler+0xd0/0x268 [<00000000d495ef94>] el0_sync+0x164/0x180 unreferenced object 0x29ff008981cc4180 (size 128): comm "qemu-kvm", pid 4043, jiffies 4294994818 (age 9796.290s) hex dump (first 32 bytes): 01 00 00 00 6b 6b 6b 6b 00 00 00 00 ad 4e ad de ....kkkk.....N.. ff ff ff ff 6b 6b 6b 6b ff ff ff ff ff ff ff ff ....kkkk........ backtrace: [<00000000917e8f8d>] slab_post_alloc_hook+0x74/0x9c [<00000000df0f2aa2>] kmem_cache_alloc_trace+0x2b4/0x3d4 [<000000005fcec025>] do_eventfd+0x54/0x1ac [<0000000082791a69>] __arm64_sys_eventfd2+0x34/0x44 [<00000000b819758c>] do_el0_svc+0x128/0x1dc [<00000000b244e810>] el0_sync_handler+0xd0/0x268 [<00000000d495ef94>] el0_sync+0x164/0x180 Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-09-09vfio/pci: Fix SR-IOV VF handling with MMIO blockingAlex Williamson
commit ebfa440ce38b7e2e04c3124aa89c8a9f4094cf21 upstream. SR-IOV VFs do not implement the memory enable bit of the command register, therefore this bit is not set in config space after pci_enable_device(). This leads to an unintended difference between PF and VF in hand-off state to the user. We can correct this by setting the initial value of the memory enable bit in our virtualized config space. There's really no need however to ever fault a user on a VF though as this would only indicate an error in the user's management of the enable bit, versus a PF where the same access could trigger hardware faults. Fixes: abafbc551fdd ("vfio-pci: Invalidate mmaps and block MMIO access on disabled memory") Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-09vfio-pci: Invalidate mmaps and block MMIO access on disabled memoryAlex Williamson
commit abafbc551fddede3e0a08dee1dcde08fc0eb8476 upstream. Accessing the disabled memory space of a PCI device would typically result in a master abort response on conventional PCI, or an unsupported request on PCI express. The user would generally see these as a -1 response for the read return data and the write would be silently discarded, possibly with an uncorrected, non-fatal AER error triggered on the host. Some systems however take it upon themselves to bring down the entire system when they see something that might indicate a loss of data, such as this discarded write to a disabled memory space. To avoid this, we want to try to block the user from accessing memory spaces while they're disabled. We start with a semaphore around the memory enable bit, where writers modify the memory enable state and must be serialized, while readers make use of the memory region and can access in parallel. Writers include both direct manipulation via the command register, as well as any reset path where the internal mechanics of the reset may both explicitly and implicitly disable memory access, and manipulation of the MSI-X configuration, where the MSI-X vector table resides in MMIO space of the device. Readers include the read and write file ops to access the vfio device fd offsets as well as memory mapped access. In the latter case, we make use of our new vma list support to zap, or invalidate, those memory mappings in order to force them to be faulted back in on access. Our semaphore usage will stall user access to MMIO spaces across internal operations like reset, but the user might experience new behavior when trying to access the MMIO space while disabled via the PCI command register. Access via read or write while disabled will return -EIO and access via memory maps will result in a SIGBUS. This is expected to be compatible with known use cases and potentially provides better error handling capabilities than present in the hardware, while avoiding the more readily accessible and severe platform error responses that might otherwise occur. Fixes: CVE-2020-12888 Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> [Ajay: Regenerated the patch for v4.19] Signed-off-by: Ajay Kaher <akaher@vmware.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-09-09vfio-pci: Fault mmaps to enable vma trackingAlex Williamson
commit 11c4cd07ba111a09f49625f9e4c851d83daf0a22 upstream. Rather than calling remap_pfn_range() when a region is mmap'd, setup a vm_ops handler to support dynamic faulting of the range on access. This allows us to manage a list of vmas actively mapping the area that we can later use to invalidate those mappings. The open callback invalidates the vma range so that all tracking is inserted in the fault handler and removed in the close handler. Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> [Ajay: Regenerated the patch for v4.19] Signed-off-by: Ajay Kaher <akaher@vmware.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-09-09vfio/type1: Support faulting PFNMAP vmasAlex Williamson
commit 41311242221e3482b20bfed10fa4d9db98d87016 upstream. With conversion to follow_pfn(), DMA mapping a PFNMAP range depends on the range being faulted into the vma. Add support to manually provide that, in the same way as done on KVM with hva_to_pfn_remapped(). Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> [Ajay: Regenerated the patch for v4.19] Signed-off-by: Ajay Kaher <akaher@vmware.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26vfio/type1: Add proper error unwind for vfio_iommu_replay()Alex Williamson
[ Upstream commit aae7a75a821a793ed6b8ad502a5890fb8e8f172d ] The vfio_iommu_replay() function does not currently unwind on error, yet it does pin pages, perform IOMMU mapping, and modify the vfio_dma structure to indicate IOMMU mapping. The IOMMU mappings are torn down when the domain is destroyed, but the other actions go on to cause trouble later. For example, the iommu->domain_list can be empty if we only have a non-IOMMU backed mdev attached. We don't currently check if the list is empty before getting the first entry in the list, which leads to a bogus domain pointer. If a vfio_dma entry is erroneously marked as iommu_mapped, we'll attempt to use that bogus pointer to retrieve the existing physical page addresses. This is the scenario that uncovered this issue, attempting to hot-add a vfio-pci device to a container with an existing mdev device and DMA mappings, one of which could not be pinned, causing a failure adding the new group to the existing container and setting the conditions for a subsequent attempt to explode. To resolve this, we can first check if the domain_list is empty so that we can reject replay of a bogus domain, should we ever encounter this inconsistent state again in the future. The real fix though is to add the necessary unwind support, which means cleaning up the current pinning if an IOMMU mapping fails, then walking back through the r-b tree of DMA entries, reading from the IOMMU which ranges are mapped, and unmapping and unpinning those ranges. To be able to do this, we also defer marking the DMA entry as IOMMU mapped until all entries are processed, in order to allow the unwind to know the disposition of each entry. Fixes: a54eb55045ae ("vfio iommu type1: Add support for mediated devices") Reported-by: Zhiyi Guo <zhguo@redhat.com> Tested-by: Zhiyi Guo <zhguo@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-25vfio/mdev: Fix reference count leak in add_mdev_supported_typeQiushi Wu
[ Upstream commit aa8ba13cae3134b8ef1c1b6879f66372531da738 ] kobject_init_and_add() takes reference even when it fails. If this function returns an error, kobject_put() must be called to properly clean up the memory associated with the object. Thus, replace kfree() by kobject_put() to fix this issue. Previous commit "b8eb718348b8" fixed a similar problem. Fixes: 7b96953bc640 ("vfio: Mediated device Core driver") Signed-off-by: Qiushi Wu <wu000273@umn.edu> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-25vfio-pci: Mask cap zeroAlex Williamson
[ Upstream commit bc138db1b96264b9c1779cf18d5a3b186aa90066 ] The PCI Code and ID Assignment Specification changed capability ID 0 from reserved to a NULL capability in the v1.1 revision. The NULL capability is defined to include only the 16-bit capability header, ie. only the ID and next pointer. Unfortunately vfio-pci creates a map of config space, where ID 0 is used to reserve the standard type 0 header. Finding an actual capability with this ID therefore results in a bogus range marked in that map and conflicts with subsequent capabilities. As this seems to be a dummy capability anyway and we already support dropping capabilities, let's hide this one rather than delving into the potentially subtle dependencies within our map. Seen on an NVIDIA Tesla T4. Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-25vfio/pci: fix memory leaks in alloc_perm_bits()Qian Cai
[ Upstream commit 3e63b94b6274324ff2e7d8615df31586de827c4e ] vfio_pci_disable() calls vfio_config_free() but forgets to call free_perm_bits() resulting in memory leaks, unreferenced object 0xc000000c4db2dee0 (size 16): comm "qemu-kvm", pid 4305, jiffies 4295020272 (age 3463.780s) hex dump (first 16 bytes): 00 00 ff 00 ff ff ff ff ff ff ff ff ff ff 00 00 ................ backtrace: [<00000000a6a4552d>] alloc_perm_bits+0x58/0xe0 [vfio_pci] [<00000000ac990549>] vfio_config_init+0xdf0/0x11b0 [vfio_pci] init_pci_cap_msi_perm at drivers/vfio/pci/vfio_pci_config.c:1125 (inlined by) vfio_msi_cap_len at drivers/vfio/pci/vfio_pci_config.c:1180 (inlined by) vfio_cap_len at drivers/vfio/pci/vfio_pci_config.c:1241 (inlined by) vfio_cap_init at drivers/vfio/pci/vfio_pci_config.c:1468 (inlined by) vfio_config_init at drivers/vfio/pci/vfio_pci_config.c:1707 [<000000006db873a1>] vfio_pci_open+0x234/0x700 [vfio_pci] [<00000000630e1906>] vfio_group_fops_unl_ioctl+0x8e0/0xb84 [vfio] [<000000009e34c54f>] ksys_ioctl+0xd8/0x130 [<000000006577923d>] sys_ioctl+0x28/0x40 [<000000006d7b1cf2>] system_call_exception+0x114/0x1e0 [<0000000008ea7dd5>] system_call_common+0xf0/0x278 unreferenced object 0xc000000c4db2e330 (size 16): comm "qemu-kvm", pid 4305, jiffies 4295020272 (age 3463.780s) hex dump (first 16 bytes): 00 ff ff 00 ff ff ff ff ff ff ff ff ff ff 00 00 ................ backtrace: [<000000004c71914f>] alloc_perm_bits+0x44/0xe0 [vfio_pci] [<00000000ac990549>] vfio_config_init+0xdf0/0x11b0 [vfio_pci] [<000000006db873a1>] vfio_pci_open+0x234/0x700 [vfio_pci] [<00000000630e1906>] vfio_group_fops_unl_ioctl+0x8e0/0xb84 [vfio] [<000000009e34c54f>] ksys_ioctl+0xd8/0x130 [<000000006577923d>] sys_ioctl+0x28/0x40 [<000000006d7b1cf2>] system_call_exception+0x114/0x1e0 [<0000000008ea7dd5>] system_call_common+0xf0/0x278 Fixes: 89e1f7d4c66d ("vfio: Add PCI device driver") Signed-off-by: Qian Cai <cai@lca.pw> [aw: rolled in follow-up patch] Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-06vfio/type1: Fix VA->PA translation for PFNMAP VMAs in vaddr_get_pfn()Sean Christopherson
commit 5cbf3264bc715e9eb384e2b68601f8c02bb9a61d upstream. Use follow_pfn() to get the PFN of a PFNMAP VMA instead of assuming that vma->vm_pgoff holds the base PFN of the VMA. This fixes a bug where attempting to do VFIO_IOMMU_MAP_DMA on an arbitrary PFNMAP'd region of memory calculates garbage for the PFN. Hilariously, this only got detected because the first "PFN" calculated by vaddr_get_pfn() is PFN 0 (vma->vm_pgoff==0), and iommu_iova_to_phys() uses PA==0 as an error, which triggers a WARN in vfio_unmap_unpin() because the translation "failed". PFN 0 is now unconditionally reserved on x86 in order to mitigate L1TF, which causes is_invalid_reserved_pfn() to return true and in turns results in vaddr_get_pfn() returning success for PFN 0. Eventually the bogus calculation runs into PFNs that aren't reserved and leads to failure in vfio_pin_map_dma(). The subsequent call to vfio_remove_dma() attempts to unmap PFN 0 and WARNs. WARNING: CPU: 8 PID: 5130 at drivers/vfio/vfio_iommu_type1.c:750 vfio_unmap_unpin+0x2e1/0x310 [vfio_iommu_type1] Modules linked in: vfio_pci vfio_virqfd vfio_iommu_type1 vfio ... CPU: 8 PID: 5130 Comm: sgx Tainted: G W 5.6.0-rc5-705d787c7fee-vfio+ #3 Hardware name: Intel Corporation Mehlow UP Server Platform/Moss Beach Server, BIOS CNLSE2R1.D00.X119.B49.1803010910 03/01/2018 RIP: 0010:vfio_unmap_unpin+0x2e1/0x310 [vfio_iommu_type1] Code: <0f> 0b 49 81 c5 00 10 00 00 e9 c5 fe ff ff bb 00 10 00 00 e9 3d fe RSP: 0018:ffffbeb5039ebda8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff9a55cbf8d480 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff9a52b771c200 RBP: 0000000000000000 R08: 0000000000000040 R09: 00000000fffffff2 R10: 0000000000000001 R11: ffff9a51fa896000 R12: 0000000184010000 R13: 0000000184000000 R14: 0000000000010000 R15: ffff9a55cb66ea08 FS: 00007f15d3830b40(0000) GS:ffff9a55d5600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000561cf39429e0 CR3: 000000084f75f005 CR4: 00000000003626e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vfio_remove_dma+0x17/0x70 [vfio_iommu_type1] vfio_iommu_type1_ioctl+0x9e3/0xa7b [vfio_iommu_type1] ksys_ioctl+0x92/0xb0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x4c/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f15d04c75d7 Code: <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 81 48 2d 00 f7 d8 64 89 01 48 Fixes: 73fa0d10d077 ("vfio: Type1 IOMMU implementation") Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-06vfio: avoid possible overflow in vfio_iommu_type1_pin_pagesYan Zhao
commit 0ea971f8dcd6dee78a9a30ea70227cf305f11ff7 upstream. add parentheses to avoid possible vaddr overflow. Fixes: a54eb55045ae ("vfio iommu type1: Add support for mediated devices") Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-27vfio/mdev: Fix aborting mdev child device removal if one failsParav Pandit
[ Upstream commit 6093e348a5e2475c5bb2e571346460f939998670 ] device_for_each_child() stops executing callback function for remaining child devices, if callback hits an error. Each child mdev device is independent of each other. While unregistering parent device, mdev core must remove all child mdev devices. Therefore, mdev_device_remove_cb() always returns success so that device_for_each_child doesn't abort if one child removal hits error. While at it, improve remove and unregister functions for below simplicity. There isn't need to pass forced flag pointer during mdev parent removal which invokes mdev_device_remove(). So simplify the flow. mdev_device_remove() is called from two paths. 1. mdev_unregister_driver() mdev_device_remove_cb() mdev_device_remove() 2. remove_store() mdev_device_remove() Fixes: 7b96953bc640 ("vfio: Mediated device Core driver") Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Parav Pandit <parav@mellanox.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27vfio/mdev: Follow correct remove sequenceParav Pandit
[ Upstream commit a6d6f4f160f76d840e59affe664b8d3159e23056 ] mdev_remove_sysfs_files() should follow exact mirror sequence of a create, similar to what is followed in error unwinding path of mdev_create_sysfs_files(). Fixes: 6a62c1dfb5c7 ("vfio/mdev: Re-order sysfs attribute creation") Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Parav Pandit <parav@mellanox.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27vfio/mdev: Avoid release parent reference during error pathParav Pandit
[ Upstream commit 60e7f2c3fe9919cee9534b422865eed49f4efb15 ] During mdev parent registration in mdev_register_device(), if parent device is duplicate, it releases the reference of existing parent device. This is incorrect. Existing parent device should not be touched. Fixes: 7b96953bc640 ("vfio: Mediated device Core driver") Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Parav Pandit <parav@mellanox.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27vfio_pci: Enable memory accesses before calling pci_map_romEric Auger
[ Upstream commit 0cfd027be1d6def4a462cdc180c055143af24069 ] pci_map_rom/pci_get_rom_size() performs memory access in the ROM. In case the Memory Space accesses were disabled, readw() is likely to trigger a synchronous external abort on some platforms. In case memory accesses were disabled, re-enable them before the call and disable them back again just after. Fixes: 89e1f7d4c66d ("vfio: Add PCI device driver") Signed-off-by: Eric Auger <eric.auger@redhat.com> Suggested-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-21vfio/pci: call irq_bypass_unregister_producer() before freeing irqJiang Yi
commit d567fb8819162099035e546b11a736e29c2af0ea upstream. Since irq_bypass_register_producer() is called after request_irq(), we should do tear-down in reverse order: irq_bypass_unregister_producer() then free_irq(). Specifically free_irq() may release resources required by the irqbypass del_producer() callback. Notably an example provided by Marc Zyngier on arm64 with GICv4 that he indicates has the potential to wedge the hardware: free_irq(irq) __free_irq(irq) irq_domain_deactivate_irq(irq) its_irq_domain_deactivate() [unmap the VLPI from the ITS] kvm_arch_irq_bypass_del_producer(cons, prod) kvm_vgic_v4_unset_forwarding(kvm, irq, ...) its_unmap_vlpi(irq) [Unmap the VLPI from the ITS (again), remap the original LPI] Signed-off-by: Jiang Yi <giangyi@amazon.com> Cc: stable@vger.kernel.org # v4.4+ Fixes: 6d7425f109d26 ("vfio: Register/unregister irq_bypass_producer") Link: https://lore.kernel.org/kvm/20191127164910.15888-1-giangyi@amazon.com Reviewed-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Eric Auger <eric.auger@redhat.com> [aw: commit log] Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-05vfio/spapr_tce: Get rid of possible infinite loopAlexey Kardashevskiy
[ Upstream commit 517ad4ae8aa93dccdb9a88c27257ecb421c9e848 ] As a part of cleanup, the SPAPR TCE IOMMU subdriver releases preregistered memory. If there is a bug in memory release, the loop in tce_iommu_release() becomes infinite; this actually happened to me. This makes the loop finite and prints a warning on every failure to make the code more bug prone. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-20vfio/pci: Mask buggy SR-IOV VF INTx supportAlex Williamson
[ Upstream commit db04264fe9bc0f2b62e036629f9afb530324b693 ] The SR-IOV spec requires that VFs must report zero for the INTx pin register as VFs are precluded from INTx support. It's much easier for the host kernel to understand whether a device is a VF and therefore whether a non-zero pin register value is bogus than it is to do the same in userspace. Override the INTx count for such devices and virtualize the pin register to provide a consistent view of the device to the user. As this is clearly a spec violation, warn about it to support hardware validation, but also provide a known whitelist as it doesn't do much good to continue complaining if the hardware vendor doesn't plan to fix it. Known devices with this issue: 8086:270c Tested-by: Gage Eads <gage.eads@intel.com> Reviewed-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-20vfio/pci: Fix potential memory leak in vfio_msi_cap_lenLi Qiang
[ Upstream commit 30ea32ab1951c80c6113f300fce2c70cd12659e4 ] Free allocated vdev->msi_perm in error path. Signed-off-by: Li Qiang <liq3ea@gmail.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-07vfio_pci: Restore original state on releasehexin
[ Upstream commit 92c8026854c25093946e0d7fe536fd9eac440f06 ] vfio_pci_enable() saves the device's initial configuration information with the intent that it is restored in vfio_pci_disable(). However, the commit referenced in Fixes: below replaced the call to __pci_reset_function_locked(), which is not wrapped in a state save and restore, with pci_try_reset_function(), which overwrites the restored device state with the current state before applying it to the device. Reinstate use of __pci_reset_function_locked() to return to the desired behavior. Fixes: 890ed578df82 ("vfio-pci: Use pci "try" reset interface") Signed-off-by: hexin <hexin15@baidu.com> Signed-off-by: Liu Qi <liuqi16@baidu.com> Signed-off-by: Zhang Yu <zhangyu31@baidu.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-15vfio: Fix WARNING "do not call blocking ops when !TASK_RUNNING"Farhan Ali
[ Upstream commit 41be3e2618174fdf3361e49e64f2bf530f40c6b0 ] vfio_dev_present() which is the condition to wait_event_interruptible_timeout(), will call vfio_group_get_device and try to acquire the mutex group->device_lock. wait_event_interruptible_timeout() will set the state of the current task to TASK_INTERRUPTIBLE, before doing the condition check. This means that we will try to acquire the mutex while already in a sleeping state. The scheduler warns us by giving the following warning: [ 4050.264464] ------------[ cut here ]------------ [ 4050.264508] do not call blocking ops when !TASK_RUNNING; state=1 set at [<00000000b33c00e2>] prepare_to_wait_event+0x14a/0x188 [ 4050.264529] WARNING: CPU: 12 PID: 35924 at kernel/sched/core.c:6112 __might_sleep+0x76/0x90 .... 4050.264756] Call Trace: [ 4050.264765] ([<000000000017bbaa>] __might_sleep+0x72/0x90) [ 4050.264774] [<0000000000b97edc>] __mutex_lock+0x44/0x8c0 [ 4050.264782] [<0000000000b9878a>] mutex_lock_nested+0x32/0x40 [ 4050.264793] [<000003ff800d7abe>] vfio_group_get_device+0x36/0xa8 [vfio] [ 4050.264803] [<000003ff800d87c0>] vfio_del_group_dev+0x238/0x378 [vfio] [ 4050.264813] [<000003ff8015f67c>] mdev_remove+0x3c/0x68 [mdev] [ 4050.264825] [<00000000008e01b0>] device_release_driver_internal+0x168/0x268 [ 4050.264834] [<00000000008de692>] bus_remove_device+0x162/0x190 [ 4050.264843] [<00000000008daf42>] device_del+0x1e2/0x368 [ 4050.264851] [<00000000008db12c>] device_unregister+0x64/0x88 [ 4050.264862] [<000003ff8015ed84>] mdev_device_remove+0xec/0x130 [mdev] [ 4050.264872] [<000003ff8015f074>] remove_store+0x6c/0xa8 [mdev] [ 4050.264881] [<000000000046f494>] kernfs_fop_write+0x14c/0x1f8 [ 4050.264890] [<00000000003c1530>] __vfs_write+0x38/0x1a8 [ 4050.264899] [<00000000003c187c>] vfs_write+0xb4/0x198 [ 4050.264908] [<00000000003c1af2>] ksys_write+0x5a/0xb0 [ 4050.264916] [<0000000000b9e270>] system_call+0xdc/0x2d8 [ 4050.264925] 4 locks held by sh/35924: [ 4050.264933] #0: 000000001ef90325 (sb_writers#4){.+.+}, at: vfs_write+0x9e/0x198 [ 4050.264948] #1: 000000005c1ab0b3 (&of->mutex){+.+.}, at: kernfs_fop_write+0x1cc/0x1f8 [ 4050.264963] #2: 0000000034831ab8 (kn->count#297){++++}, at: kernfs_remove_self+0x12e/0x150 [ 4050.264979] #3: 00000000e152484f (&dev->mutex){....}, at: device_release_driver_internal+0x5c/0x268 [ 4050.264993] Last Breaking-Event-Address: [ 4050.265002] [<000000000017bbaa>] __might_sleep+0x72/0x90 [ 4050.265010] irq event stamp: 7039 [ 4050.265020] hardirqs last enabled at (7047): [<00000000001cee7a>] console_unlock+0x6d2/0x740 [ 4050.265029] hardirqs last disabled at (7054): [<00000000001ce87e>] console_unlock+0xd6/0x740 [ 4050.265040] softirqs last enabled at (6416): [<0000000000b8fe26>] __udelay+0xb6/0x100 [ 4050.265049] softirqs last disabled at (6415): [<0000000000b8fe06>] __udelay+0x96/0x100 [ 4050.265057] ---[ end trace d04a07d39d99a9f9 ]--- Let's fix this as described in the article https://lwn.net/Articles/628628/. Signed-off-by: Farhan Ali <alifm@linux.ibm.com> [remove now redundant vfio_dev_present()] Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-08vfio/pci: use correct format charactersLouis Taylor
[ Upstream commit 426b046b748d1f47e096e05bdcc6fb4172791307 ] When compiling with -Wformat, clang emits the following warnings: drivers/vfio/pci/vfio_pci.c:1601:5: warning: format specifies type 'unsigned short' but the argument has type 'unsigned int' [-Wformat] vendor, device, subvendor, subdevice, ^~~~~~ drivers/vfio/pci/vfio_pci.c:1601:13: warning: format specifies type 'unsigned short' but the argument has type 'unsigned int' [-Wformat] vendor, device, subvendor, subdevice, ^~~~~~ drivers/vfio/pci/vfio_pci.c:1601:21: warning: format specifies type 'unsigned short' but the argument has type 'unsigned int' [-Wformat] vendor, device, subvendor, subdevice, ^~~~~~~~~ drivers/vfio/pci/vfio_pci.c:1601:32: warning: format specifies type 'unsigned short' but the argument has type 'unsigned int' [-Wformat] vendor, device, subvendor, subdevice, ^~~~~~~~~ drivers/vfio/pci/vfio_pci.c:1605:5: warning: format specifies type 'unsigned short' but the argument has type 'unsigned int' [-Wformat] vendor, device, subvendor, subdevice, ^~~~~~ drivers/vfio/pci/vfio_pci.c:1605:13: warning: format specifies type 'unsigned short' but the argument has type 'unsigned int' [-Wformat] vendor, device, subvendor, subdevice, ^~~~~~ drivers/vfio/pci/vfio_pci.c:1605:21: warning: format specifies type 'unsigned short' but the argument has type 'unsigned int' [-Wformat] vendor, device, subvendor, subdevice, ^~~~~~~~~ drivers/vfio/pci/vfio_pci.c:1605:32: warning: format specifies type 'unsigned short' but the argument has type 'unsigned int' [-Wformat] vendor, device, subvendor, subdevice, ^~~~~~~~~ The types of these arguments are unconditionally defined, so this patch updates the format character to the correct ones for unsigned ints. Link: https://github.com/ClangBuiltLinux/linux/issues/378 Signed-off-by: Louis Taylor <louis@kragniz.eu> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-02vfio/type1: Limit DMA mappings per containerAlex Williamson
commit 492855939bdb59c6f947b0b5b44af9ad82b7e38c upstream. Memory backed DMA mappings are accounted against a user's locked memory limit, including multiple mappings of the same memory. This accounting bounds the number of such mappings that a user can create. However, DMA mappings that are not backed by memory, such as DMA mappings of device MMIO via mmaps, do not make use of page pinning and therefore do not count against the user's locked memory limit. These mappings still consume memory, but the memory is not well associated to the process for the purpose of oom killing a task. To add bounding on this use case, we introduce a limit to the total number of concurrent DMA mappings that a user is allowed to create. This limit is exposed as a tunable module option where the default value of 64K is expected to be well in excess of any reasonable use case (a large virtual machine configuration would typically only make use of tens of concurrent mappings). This fixes CVE-2019-3882. Reviewed-by: Eric Auger <eric.auger@redhat.com> Tested-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-16vfio/type1: Fix unmap overflow off-by-oneAlex Williamson
commit 58fec830fc19208354895d9832785505046d6c01 upstream. The below referenced commit adds a test for integer overflow, but in doing so prevents the unmap ioctl from ever including the last page of the address space. Subtract one to compare to the last address of the unmap to avoid the overflow and wrap-around. Fixes: 71a7d3d78e3c ("vfio/type1: silence integer overflow warning") Link: https://bugzilla.redhat.com/show_bug.cgi?id=1662291 Cc: stable@vger.kernel.org # v4.15+ Reported-by: Pei Zhang <pezhang@redhat.com> Debugged-by: Peter Xu <peterx@redhat.com> Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Peter Xu <peterx@redhat.com> Tested-by: Peter Xu <peterx@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-17Merge tag 'powerpc-4.19-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Notable changes: - A fix for a bug in our page table fragment allocator, where a page table page could be freed and reallocated for something else while still in use, leading to memory corruption etc. The fix reuses pt_mm in struct page (x86 only) for a powerpc only refcount. - Fixes to our pkey support. Several are user-visible changes, but bring us in to line with x86 behaviour and/or fix outright bugs. Thanks to Florian Weimer for reporting many of these. - A series to improve the hvc driver & related OPAL console code, which have been seen to cause hardlockups at times. The hvc driver changes in particular have been in linux-next for ~month. - Increase our MAX_PHYSMEM_BITS to 128TB when SPARSEMEM_VMEMMAP=y. - Remove Power8 DD1 and Power9 DD1 support, neither chip should be in use anywhere other than as a paper weight. - An optimised memcmp implementation using Power7-or-later VMX instructions - Support for barrier_nospec on some NXP CPUs. - Support for flushing the count cache on context switch on some IBM CPUs (controlled by firmware), as a Spectre v2 mitigation. - A series to enhance the information we print on unhandled signals to bring it into line with other arches, including showing the offending VMA and dumping the instructions around the fault. Thanks to: Aaro Koskinen, Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Alexey Spirkov, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Arnd Bergmann, Bartosz Golaszewski, Benjamin Herrenschmidt, Bharat Bhushan, Bjoern Noetel, Boqun Feng, Breno Leitao, Bryant G. Ly, Camelia Groza, Christophe Leroy, Christoph Hellwig, Cyril Bur, Dan Carpenter, Daniel Klamt, Darren Stevens, Dave Young, David Gibson, Diana Craciun, Finn Thain, Florian Weimer, Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven, Geoff Levand, Guenter Roeck, Gustavo Romero, Haren Myneni, Hari Bathini, Joel Stanley, Jonathan Neuschäfer, Kees Cook, Madhavan Srinivasan, Mahesh Salgaonkar, Markus Elfring, Mathieu Malaterre, Mauro S. M. Rodrigues, Michael Hanselmann, Michael Neuling, Michael Schmitz, Mukesh Ojha, Murilo Opsfelder Araujo, Nicholas Piggin, Parth Y Shah, Paul Mackerras, Paul Menzel, Ram Pai, Randy Dunlap, Rashmica Gupta, Reza Arbab, Rodrigo R. Galvao, Russell Currey, Sam Bobroff, Scott Wood, Shilpasri G Bhat, Simon Guo, Souptick Joarder, Stan Johnson, Thiago Jung Bauermann, Tyrel Datwyler, Vaibhav Jain, Vasant Hegde, Venkat Rao, zhong jiang" * tag 'powerpc-4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (234 commits) powerpc/mm/book3s/radix: Add mapping statistics powerpc/uaccess: Enable get_user(u64, *p) on 32-bit powerpc/mm/hash: Remove unnecessary do { } while(0) loop powerpc/64s: move machine check SLB flushing to mm/slb.c powerpc/powernv/idle: Fix build error powerpc/mm/tlbflush: update the mmu_gather page size while iterating address range powerpc/mm: remove warning about ‘type’ being set powerpc/32: Include setup.h header file to fix warnings powerpc: Move `path` variable inside DEBUG_PROM powerpc/powermac: Make some functions static powerpc/powermac: Remove variable x that's never read cxl: remove a dead branch powerpc/powermac: Add missing include of header pmac.h powerpc/kexec: Use common error handling code in setup_new_fdt() powerpc/xmon: Add address lookup for percpu symbols powerpc/mm: remove huge_pte_offset_and_shift() prototype powerpc/lib: Use patch_site to patch copy_32 functions once cache is enabled powerpc/pseries: Fix endianness while restoring of r3 in MCE handler. powerpc/fadump: merge adjacent memory ranges to reduce PT_LOAD segements powerpc/fadump: handle crash memory ranges array index overflow ...
2018-08-16Merge tag 'vfio-v4.19-rc1' of git://github.com/awilliam/linux-vfioLinus Torvalds
Pull VFIO updates from Alex Williamson: - mark switch fall-through cases (Gustavo A. R. Silva) - disable binding SR-IOV enabled PFs (Alex Williamson) * tag 'vfio-v4.19-rc1' of git://github.com/awilliam/linux-vfio: vfio-pci: Disable binding to PFs with SR-IOV enabled vfio: Mark expected switch fall-throughs
2018-08-16Merge tag 'pci-v4.19-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull pci updates from Bjorn Helgaas: - Decode AER errors with names similar to "lspci" (Tyler Baicar) - Expose AER statistics in sysfs (Rajat Jain) - Clear AER status bits selectively based on the type of recovery (Oza Pawandeep) - Honor "pcie_ports=native" even if HEST sets FIRMWARE_FIRST (Alexandru Gagniuc) - Don't clear AER status bits if we're using the "Firmware-First" strategy where firmware owns the registers (Alexandru Gagniuc) - Use sysfs_match_string() to simplify ASPM sysfs parsing (Andy Shevchenko) - Remove unnecessary includes of <linux/pci-aspm.h> (Bjorn Helgaas) - Defer DPC event handling to work queue (Keith Busch) - Use threaded IRQ for DPC bottom half (Keith Busch) - Print AER status while handling DPC events (Keith Busch) - Work around IDT switch ACS Source Validation erratum (James Puthukattukaran) - Emit diagnostics for all cases of PCIe Link downtraining (Links operating slower than they're capable of) (Alexandru Gagniuc) - Skip VFs when configuring Max Payload Size (Myron Stowe) - Reduce Root Port Max Payload Size if necessary when hot-adding a device below it (Myron Stowe) - Simplify SHPC existence/permission checks (Bjorn Helgaas) - Remove hotplug sample skeleton driver (Lukas Wunner) - Convert pciehp to threaded IRQ handling (Lukas Wunner) - Improve pciehp tolerance of missed events and initially unstable links (Lukas Wunner) - Clear spurious pciehp events on resume (Lukas Wunner) - Add pciehp runtime PM support, including for Thunderbolt controllers (Lukas Wunner) - Support interrupts from pciehp bridges in D3hot (Lukas Wunner) - Mark fall-through switch cases before enabling -Wimplicit-fallthrough (Gustavo A. R. Silva) - Move DMA-debug PCI init from arch code to PCI core (Christoph Hellwig) - Fix pci_request_irq() usage of IRQF_ONESHOT when no handler is supplied (Heiner Kallweit) - Unify PCI and DMA direction #defines (Shunyong Yang) - Add PCI_DEVICE_DATA() macro (Andy Shevchenko) - Check for VPD completion before checking for timeout (Bert Kenward) - Limit Netronome NFP5000 config space size to work around erratum (Jakub Kicinski) - Set IRQCHIP_ONESHOT_SAFE for PCI MSI irqchips (Heiner Kallweit) - Document ACPI description of PCI host bridges (Bjorn Helgaas) - Add "pci=disable_acs_redir=" parameter to disable ACS redirection for peer-to-peer DMA support (we don't have the peer-to-peer support yet; this is just one piece) (Logan Gunthorpe) - Clean up devm_of_pci_get_host_bridge_resources() resource allocation (Jan Kiszka) - Fixup resizable BARs after suspend/resume (Christian König) - Make "pci=earlydump" generic (Sinan Kaya) - Fix ROM BAR access routines to stay in bounds and check for signature correctly (Rex Zhu) - Add DMA alias quirk for Microsemi Switchtec NTB (Doug Meyer) - Expand documentation for pci_add_dma_alias() (Logan Gunthorpe) - To avoid bus errors, enable PASID only if entire path supports End-End TLP prefixes (Sinan Kaya) - Unify slot and bus reset functions and remove hotplug knowledge from callers (Sinan Kaya) - Add Function-Level Reset quirks for Intel and Samsung NVMe devices to fix guest reboot issues (Alex Williamson) - Add function 1 DMA alias quirk for Marvell 88SS9183 PCIe SSD Controller (Bjorn Helgaas) - Remove Xilinx AXI-PCIe host bridge arch dependency (Palmer Dabbelt) - Remove Aardvark outbound window configuration (Evan Wang) - Fix Aardvark bridge window sizing issue (Zachary Zhang) - Convert Aardvark to use pci_host_probe() to reduce code duplication (Thomas Petazzoni) - Correct the Cadence cdns_pcie_writel() signature (Alan Douglas) - Add Cadence support for optional generic PHYs (Alan Douglas) - Add Cadence power management ops (Alan Douglas) - Remove redundant variable from Cadence driver (Colin Ian King) - Add Kirin MSI support (Xiaowei Song) - Drop unnecessary root_bus_nr setting from exynos, imx6, keystone, armada8k, artpec6, designware-plat, histb, qcom, spear13xx (Shawn Guo) - Move link notification settings from DesignWare core to individual drivers (Gustavo Pimentel) - Add endpoint library MSI-X interfaces (Gustavo Pimentel) - Correct signature of endpoint library IRQ interfaces (Gustavo Pimentel) - Add DesignWare endpoint library MSI-X callbacks (Gustavo Pimentel) - Add endpoint library MSI-X test support (Gustavo Pimentel) - Remove unnecessary GFP_ATOMIC from Hyper-V "new child" allocation (Jia-Ju Bai) - Add more devices to Broadcom PAXC quirk (Ray Jui) - Work around corrupted Broadcom PAXC config space to enable SMMU and GICv3 ITS (Ray Jui) - Disable MSI parsing to work around broken Broadcom PAXC logic in some devices (Ray Jui) - Hide unconfigured functions to work around a Broadcom PAXC defect (Ray Jui) - Lower iproc log level to reduce console output during boot (Ray Jui) - Fix mobiveil iomem/phys_addr_t type usage (Lorenzo Pieralisi) - Fix mobiveil missing include file (Lorenzo Pieralisi) - Add mobiveil Kconfig/Makefile support (Lorenzo Pieralisi) - Fix mvebu I/O space remapping issues (Thomas Petazzoni) - Use generic pci_host_bridge in mvebu instead of ARM-specific API (Thomas Petazzoni) - Whitelist VMD devices with fast interrupt handlers to avoid sharing vectors with slow handlers (Keith Busch) * tag 'pci-v4.19-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (153 commits) PCI/AER: Don't clear AER bits if error handling is Firmware-First PCI: Limit config space size for Netronome NFP5000 PCI/MSI: Set IRQCHIP_ONESHOT_SAFE for PCI-MSI irqchips PCI/VPD: Check for VPD access completion before checking for timeout PCI: Add PCI_DEVICE_DATA() macro to fully describe device ID entry PCI: Match Root Port's MPS to endpoint's MPSS as necessary PCI: Skip MPS logic for Virtual Functions (VFs) PCI: Add function 1 DMA alias quirk for Marvell 88SS9183 PCI: Check for PCIe Link downtraining PCI: Add ACS Redirect disable quirk for Intel Sunrise Point PCI: Add device-specific ACS Redirect disable infrastructure PCI: Convert device-specific ACS quirks from NULL termination to ARRAY_SIZE PCI: Add "pci=disable_acs_redir=" parameter for peer-to-peer support PCI: Allow specifying devices using a base bus and path of devfns PCI: Make specifying PCI devices in kernel parameters reusable PCI: Hide ACS quirk declarations inside PCI core PCI: Delay after FLR of Intel DC P3700 NVMe PCI: Disable Samsung SM961/PM961 NVMe before FLR PCI: Export pcie_has_flr() PCI: mvebu: Drop bogus comment above mvebu_pcie_map_registers() ...
2018-08-13Merge branch 'fixes' into nextMichael Ellerman
Merge our fixes branch from the 4.18 cycle to resolve some minor conflicts.
2018-08-06vfio-pci: Disable binding to PFs with SR-IOV enabledAlex Williamson
We expect to receive PFs with SR-IOV disabled, however some host drivers leave SR-IOV enabled at unbind. This puts us in a state where we can potentially assign both the PF and the VF, leading to both functionality as well as security concerns due to lack of managing the SR-IOV state as well as vendor dependent isolation from the PF to VF. If we were to attempt to actively disable SR-IOV on driver probe, we risk VF bound drivers blocking, potentially risking live lock scenarios. Therefore simply refuse to bind to PFs with SR-IOV enabled with a warning message indicating the issue. Users can resolve this by re-binding to the host driver and disabling SR-IOV before attempting to use the device with vfio-pci. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-08-06vfio: Mark expected switch fall-throughsGustavo A. R. Silva
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-07-21Merge tag 'powerpc-4.18-4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: "Two regression fixes, one for xmon disassembly formatting and the other to fix the E500 build. Two commits to fix a potential security issue in the VFIO code under obscure circumstances. And finally a fix to the Power9 idle code to restore SPRG3, which is user visible and used for sched_getcpu(). Thanks to: Alexey Kardashevskiy, David Gibson. Gautham R. Shenoy, James Clarke" * tag 'powerpc-4.18-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/powernv: Fix save/restore of SPRG3 on entry/exit from stop (idle) powerpc/Makefile: Assemble with -me500 when building for E500 KVM: PPC: Check if IOMMU page is contained in the pinned physical page vfio/spapr: Use IOMMU pageshift rather than pagesize powerpc/xmon: Fix disassembly since printf changes
2018-07-19PCI: Rename pci_try_reset_bus() to pci_reset_bus()Sinan Kaya
Now that the old implementation of pci_reset_bus() is gone, replace pci_try_reset_bus() with pci_reset_bus(). Compared to the old implementation, new code will fail immmediately with -EAGAIN if object lock cannot be obtained. Signed-off-by: Sinan Kaya <okaya@codeaurora.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19PCI: Unify try slot and bus reset APISinan Kaya
Drivers are expected to call pci_try_reset_slot() or pci_try_reset_bus() by querying if a system supports hotplug or not. A survey showed that most drivers don't do this and we are leaking hotplug capability to the user. Hide pci_try_slot_reset() from drivers and embed into pci_try_bus_reset(). Change pci_try_reset_bus() parameter from struct pci_bus to struct pci_dev. Signed-off-by: Sinan Kaya <okaya@codeaurora.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-18vfio/pci: Fix potential Spectre v1Gustavo A. R. Silva
info.index can be indirectly controlled by user-space, hence leading to a potential exploitation of the Spectre variant 1 vulnerability. This issue was detected with the help of Smatch: drivers/vfio/pci/vfio_pci.c:734 vfio_pci_ioctl() warn: potential spectre issue 'vdev->region' Fix this by sanitizing info.index before indirectly using it to index vdev->region Notice that given that speculation windows are large, the policy is to kill the speculation on the first load and not worry if it can be completed with a dependent load/store [1]. [1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2 Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-07-18KVM: PPC: Check if IOMMU page is contained in the pinned physical pageAlexey Kardashevskiy
A VM which has: - a DMA capable device passed through to it (eg. network card); - running a malicious kernel that ignores H_PUT_TCE failure; - capability of using IOMMU pages bigger that physical pages can create an IOMMU mapping that exposes (for example) 16MB of the host physical memory to the device when only 64K was allocated to the VM. The remaining 16MB - 64K will be some other content of host memory, possibly including pages of the VM, but also pages of host kernel memory, host programs or other VMs. The attacking VM does not control the location of the page it can map, and is only allowed to map as many pages as it has pages of RAM. We already have a check in drivers/vfio/vfio_iommu_spapr_tce.c that an IOMMU page is contained in the physical page so the PCI hardware won't get access to unassigned host memory; however this check is missing in the KVM fastpath (H_PUT_TCE accelerated code). We were lucky so far and did not hit this yet as the very first time when the mapping happens we do not have tbl::it_userspace allocated yet and fall back to the userspace which in turn calls VFIO IOMMU driver, this fails and the guest does not retry, This stores the smallest preregistered page size in the preregistered region descriptor and changes the mm_iommu_xxx API to check this against the IOMMU page size. This calculates maximum page size as a minimum of the natural region alignment and compound page size. For the page shift this uses the shift returned by find_linux_pte() which indicates how the page is mapped to the current userspace - if the page is huge and this is not a zero, then it is a leaf pte and the page is mapped within the range. Fixes: 121f80ba68f1 ("KVM: PPC: VFIO: Add in-kernel acceleration for VFIO") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-18vfio/spapr: Use IOMMU pageshift rather than pagesizeAlexey Kardashevskiy
The size is always equal to 1 page so let's use this. Later on this will be used for other checks which use page shifts to check the granularity of access. This should cause no behavioral change. Cc: stable@vger.kernel.org # v4.12+ Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-16powerpc/powernv/ioda: Allocate indirect TCE levels on demandAlexey Kardashevskiy
At the moment we allocate the entire TCE table, twice (hardware part and userspace translation cache). This normally works as we normally have contigous memory and the guest will map entire RAM for 64bit DMA. However if we have sparse RAM (one example is a memory device), then we will allocate TCEs which will never be used as the guest only maps actual memory for DMA. If it is a single level TCE table, there is nothing we can really do but if it a multilevel table, we can skip allocating TCEs we know we won't need. This adds ability to allocate only first level, saving memory. This changes iommu_table::free() to avoid allocating of an extra level; iommu_table::set() will do this when needed. This adds @alloc parameter to iommu_table::exchange() to tell the callback if it can allocate an extra level; the flag is set to "false" for the realmode KVM handlers of H_PUT_TCE hcalls and the callback returns H_TOO_HARD. This still requires the entire table to be counted in mm::locked_vm. To be conservative, this only does on-demand allocation when the usespace cache table is requested which is the case of VFIO. The example math for a system replicating a powernv setup with NVLink2 in a guest: 16GB RAM mapped at 0x0 128GB GPU RAM window (16GB of actual RAM) mapped at 0x244000000000 the table to cover that all with 64K pages takes: (((0x244000000000 + 0x2000000000) >> 16)*8)>>20 = 4556MB If we allocate only necessary TCE levels, we will only need: (((0x400000000 + 0x400000000) >> 16)*8)>>20 = 4MB (plus some for indirect levels). Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>