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* xen/pirq: fix error path cleanup when binding MSIsRoger Pau Monne2018-06-161-2/+2
| | | | | | | | | | | | | | | | | | | | | | commit 910f8befdf5bccf25287d9f1743e3e546bcb7ce0 upstream. Current cleanup in the error path of xen_bind_pirq_msi_to_irq is wrong. First of all there's an off-by-one in the cleanup loop, which can lead to unbinding wrong IRQs. Secondly IRQs not bound won't be freed, thus leaking IRQ numbers. Note that there's no need to differentiate between bound and unbound IRQs when freeing them, __unbind_from_irq will deal with both of them correctly. Fixes: 4892c9b4ada9f9 ("xen: add support for MSI message groups") Reported-by: Hooman Mirhadi <mirhadih@amazon.com> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Amit Shah <aams@amazon.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xen: Add xen_arch_suspend()Ben Hutchings2018-06-161-3/+6
| | | | | | | | | | | This is based on commit 2b953a5e994ce279904ec70220f7d4f31d380a0a upstream, "xen: Suspend ticks on all CPUs during suspend", but excluding the bug fix in that commit which is not needed in 3.16. We only need the xen_arch_suspend() hook for the following fix. Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xen/events: events_fifo: Don't use {get,put}_cpu() in xen_evtchn_fifo_init()Julien Grall2017-11-261-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 22f12f0df802cea865672d8f39fbebdc03981050 upstream. When booting Linux as Xen guest with CONFIG_DEBUG_ATOMIC, the following splat appears: [ 0.002323] Mountpoint-cache hash table entries: 1024 (order: 1, 8192 bytes) [ 0.019717] ASID allocator initialised with 65536 entries [ 0.020019] xen:grant_table: Grant tables using version 1 layout [ 0.020051] Grant table initialized [ 0.020069] BUG: sleeping function called from invalid context at /data/src/linux/mm/page_alloc.c:4046 [ 0.020100] in_atomic(): 1, irqs_disabled(): 0, pid: 1, name: swapper/0 [ 0.020123] no locks held by swapper/0/1. [ 0.020143] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.13.0-rc5 #598 [ 0.020166] Hardware name: FVP Base (DT) [ 0.020182] Call trace: [ 0.020199] [<ffff00000808a5c0>] dump_backtrace+0x0/0x270 [ 0.020222] [<ffff00000808a95c>] show_stack+0x24/0x30 [ 0.020244] [<ffff000008c1ef20>] dump_stack+0xb8/0xf0 [ 0.020267] [<ffff0000081128c0>] ___might_sleep+0x1c8/0x1f8 [ 0.020291] [<ffff000008112948>] __might_sleep+0x58/0x90 [ 0.020313] [<ffff0000082171b8>] __alloc_pages_nodemask+0x1c0/0x12e8 [ 0.020338] [<ffff00000827a110>] alloc_page_interleave+0x38/0x88 [ 0.020363] [<ffff00000827a904>] alloc_pages_current+0xdc/0xf0 [ 0.020387] [<ffff000008211f38>] __get_free_pages+0x28/0x50 [ 0.020411] [<ffff0000086566a4>] evtchn_fifo_alloc_control_block+0x2c/0xa0 [ 0.020437] [<ffff0000091747b0>] xen_evtchn_fifo_init+0x38/0xb4 [ 0.020461] [<ffff0000091746c0>] xen_init_IRQ+0x44/0xc8 [ 0.020484] [<ffff000009128adc>] xen_guest_init+0x250/0x300 [ 0.020507] [<ffff000008083974>] do_one_initcall+0x44/0x130 [ 0.020531] [<ffff000009120df8>] kernel_init_freeable+0x120/0x288 [ 0.020556] [<ffff000008c31ca8>] kernel_init+0x18/0x110 [ 0.020578] [<ffff000008083710>] ret_from_fork+0x10/0x40 [ 0.020606] xen:events: Using FIFO-based ABI [ 0.020658] Xen: initializing cpu0 [ 0.027727] Hierarchical SRCU implementation. [ 0.036235] EFI services will not be available. [ 0.043810] smp: Bringing up secondary CPUs ... This is because get_cpu() in xen_evtchn_fifo_init() will disable preemption, but __get_free_page() might sleep (GFP_ATOMIC is not set). xen_evtchn_fifo_init() will always be called before SMP is initialized, so {get,put}_cpu() could be replaced by a simple smp_processor_id(). This also avoid to modify evtchn_fifo_alloc_control_block that will be called in other context. Signed-off-by: Julien Grall <julien.grall@arm.com> Reported-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Fixes: 1fe565517b57 ("xen/events: use the FIFO-based ABI if available") Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xen: fix bio vec mergingRoger Pau Monne2017-09-151-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 462cdace790ac2ed6aad1b19c9c0af0143b6aab0 upstream. The current test for bio vec merging is not fully accurate and can be tricked into merging bios when certain grant combinations are used. The result of these malicious bio merges is a bio that extends past the memory page used by any of the originating bios. Take into account the following scenario, where a guest creates two grant references that point to the same mfn, ie: grant 1 -> mfn A, grant 2 -> mfn A. These references are then used in a PV block request, and mapped by the backend domain, thus obtaining two different pfns that point to the same mfn, pfn B -> mfn A, pfn C -> mfn A. If those grants happen to be used in two consecutive sectors of a disk IO operation becoming two different bios in the backend domain, the checks in xen_biovec_phys_mergeable will succeed, because bfn1 == bfn2 (they both point to the same mfn). However due to the bio merging, the backend domain will end up with a bio that expands past mfn A into mfn A + 1. Fix this by making sure the check in xen_biovec_phys_mergeable takes into account the offset and the length of the bio, this basically replicates whats done in __BIOVEC_PHYS_MERGEABLE using mfns (bus addresses). While there also remove the usage of __BIOVEC_PHYS_MERGEABLE, since that's already checked by the callers of xen_biovec_phys_mergeable. Reported-by: "Jan H. Schönherr" <jschoenh@amazon.de> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [bwh: Backported to 3.16: - s/bfn/mfn/g - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xen/acpi: upload PM state from init-domain to XenAnkur Arora2017-07-181-8/+26
| | | | | | | | | | | | | | | | | | | | | | commit 1914f0cd203c941bba72f9452c8290324f1ef3dc upstream. This was broken in commit cd979883b9ed ("xen/acpi-processor: fix enabling interrupts on syscore_resume"). do_suspend (from xen/manage.c) and thus xen_resume_notifier never get called on the initial-domain at resume (it is if running as guest.) The rationale for the breaking change was that upload_pm_data() potentially does blocking work in syscore_resume(). This patch addresses the original issue by scheduling upload_pm_data() to execute in workqueue context. Cc: Stanislaw Gruszka <sgruszka@redhat.com> Based-on-patch-by: Konrad Wilk <konrad.wilk@oracle.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xen/gntdev: Use VM_MIXEDMAP instead of VM_IO to avoid NUMA balancingBoris Ostrovsky2017-03-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 30faaafdfa0c754c91bac60f216c9f34a2bfdf7e upstream. Commit 9c17d96500f7 ("xen/gntdev: Grant maps should not be subject to NUMA balancing") set VM_IO flag to prevent grant maps from being subjected to NUMA balancing. It was discovered recently that this flag causes get_user_pages() to always fail with -EFAULT. check_vma_flags __get_user_pages __get_user_pages_locked __get_user_pages_unlocked get_user_pages_fast iov_iter_get_pages dio_refill_pages do_direct_IO do_blockdev_direct_IO do_blockdev_direct_IO ext4_direct_IO_read generic_file_read_iter aio_run_iocb (which can happen if guest's vdisk has direct-io-safe option). To avoid this let's use VM_MIXEDMAP flag instead --- it prevents NUMA balancing just as VM_IO does and has no effect on check_vma_flags(). Reported-by: Olaf Hering <olaf@aepfle.de> Suggested-by: Hugh Dickins <hughd@google.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Acked-by: Hugh Dickins <hughd@google.com> Tested-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xenbus: don't look up transaction IDs for ordinary writesJan Beulich2016-11-201-1/+1
| | | | | | | | | | | | | | | commit 9a035a40f7f3f6708b79224b86c5777a3334f7ea upstream. This should really only be done for XS_TRANSACTION_END messages, or else at least some of the xenstore-* tools don't work anymore. Fixes: 0beef634b8 ("xenbus: don't BUG() on user mode induced condition") Reported-by: Richard Schütz <rschuetz@uni-koblenz.de> Signed-off-by: Jan Beulich <jbeulich@suse.com> Tested-by: Richard Schütz <rschuetz@uni-koblenz.de> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: Ed Swierk <eswierk@skyportsystems.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xenbus: don't BUG() on user mode induced conditionJan Beulich2016-11-201-6/+8
| | | | | | | | | | | | | | | commit 0beef634b86a1350c31da5fcc2992f0d7c8a622b upstream. Inability to locate a user mode specified transaction ID should not lead to a kernel crash. For other than XS_TRANSACTION_START also don't issue anything to xenbus if the specified ID doesn't match that of any active transaction. Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: Ed Swierk <eswierk@skyportsystems.com> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xen/acpi: allow xen-acpi-processor driver to load on Xen 4.7Jan Beulich2016-08-221-32/+3
| | | | | | | | | | | | | | | | | | | commit 6f2d9d99213514360034c6d52d2c3919290b3504 upstream. As of Xen 4.7 PV CPUID doesn't expose either of CPUID[1].ECX[7] and CPUID[0x80000007].EDX[7] anymore, causing the driver to fail to load on both Intel and AMD systems. Doing any kind of hardware capability checks in the driver as a prerequisite was wrong anyway: With the hypervisor being in charge, all such checking should be done by it. If ACPI data gets uploaded despite some missing capability, the hypervisor is free to ignore part or all of that data. Ditch the entire check_prereq() function, and do the only valid check (xen_initial_domain()) in the caller in its place. Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xenbus: don't bail early from xenbus_dev_request_and_reply()Jan Beulich2016-08-221-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 7469be95a487319514adce2304ad2af3553d2fc9 upstream. xenbus_dev_request_and_reply() needs to track whether a transaction is open. For XS_TRANSACTION_START messages it calls transaction_start() and for XS_TRANSACTION_END messages it calls transaction_end(). If sending an XS_TRANSACTION_START message fails or responds with an an error, the transaction is not open and transaction_end() must be called. If sending an XS_TRANSACTION_END message fails, the transaction is still open, but if an error response is returned the transaction is closed. Commit 027bd7e89906 ("xen/xenbus: Avoid synchronous wait on XenBus stalling shutdown/restart") introduced a regression where failed XS_TRANSACTION_START messages were leaving the transaction open. This can cause problems with suspend (and migration) as all transactions must be closed before suspending. It appears that the problematic change was added accidentally, so just remove it. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xen/pciback: Fix conf_space read/write overlap check.Andrey Grodzovsky2016-08-221-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | commit 02ef871ecac290919ea0c783d05da7eedeffc10e upstream. Current overlap check is evaluating to false a case where a filter field is fully contained (proper subset) of a r/w request. This change applies classical overlap check instead to include all the scenarios. More specifically, for (Hilscher GmbH CIFX 50E-DP(M/S)) device driver the logic is such that the entire confspace is read and written in 4 byte chunks. In this case as an example, CACHE_LINE_SIZE, LATENCY_TIMER and PCI_BIST are arriving together in one call to xen_pcibk_config_write() with offset == 0xc and size == 4. With the exsisting overlap check the LATENCY_TIMER field (offset == 0xd, length == 1) is fully contained in the write request and hence is excluded from write, which is incorrect. Signed-off-by: Andrey Grodzovsky <andrey2805@gmail.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Jan Beulich <JBeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xen/events: Don't move disabled irqsRoss Lagerwall2016-08-221-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit f0f393877c71ad227d36705d61d1e4062bc29cf5 upstream. Commit ff1e22e7a638 ("xen/events: Mask a moving irq") open-coded irq_move_irq() but left out checking if the IRQ is disabled. This broke resuming from suspend since it tries to move a (disabled) irq without holding the IRQ's desc->lock. Fix it by adding in a check for disabled IRQs. The resulting stacktrace was: kernel BUG at /build/linux-UbQGH5/linux-4.4.0/kernel/irq/migration.c:31! invalid opcode: 0000 [#1] SMP Modules linked in: xenfs xen_privcmd ... CPU: 0 PID: 9 Comm: migration/0 Not tainted 4.4.0-22-generic #39-Ubuntu Hardware name: Xen HVM domU, BIOS 4.6.1-xs125180 05/04/2016 task: ffff88003d75ee00 ti: ffff88003d7bc000 task.ti: ffff88003d7bc000 RIP: 0010:[<ffffffff810e26e2>] [<ffffffff810e26e2>] irq_move_masked_irq+0xd2/0xe0 RSP: 0018:ffff88003d7bfc50 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff88003d40ba00 RCX: 0000000000000001 RDX: 0000000000000001 RSI: 0000000000000100 RDI: ffff88003d40bad8 RBP: ffff88003d7bfc68 R08: 0000000000000000 R09: ffff88003d000000 R10: 0000000000000000 R11: 000000000000023c R12: ffff88003d40bad0 R13: ffffffff81f3a4a0 R14: 0000000000000010 R15: 00000000ffffffff FS: 0000000000000000(0000) GS:ffff88003da00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd4264de624 CR3: 0000000037922000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffff88003d40ba38 0000000000000024 0000000000000000 ffff88003d7bfca0 ffffffff814c8d92 00000010813ef89d 00000000805ea732 0000000000000009 0000000000000024 ffff88003cc39b80 ffff88003d7bfce0 ffffffff814c8f66 Call Trace: [<ffffffff814c8d92>] eoi_pirq+0xb2/0xf0 [<ffffffff814c8f66>] __startup_pirq+0xe6/0x150 [<ffffffff814ca659>] xen_irq_resume+0x319/0x360 [<ffffffff814c7e75>] xen_suspend+0xb5/0x180 [<ffffffff81120155>] multi_cpu_stop+0xb5/0xe0 [<ffffffff811200a0>] ? cpu_stop_queue_work+0x80/0x80 [<ffffffff811203d0>] cpu_stopper_thread+0xb0/0x140 [<ffffffff810a94e6>] ? finish_task_switch+0x76/0x220 [<ffffffff810ca731>] ? __raw_callee_save___pv_queued_spin_unlock+0x11/0x20 [<ffffffff810a3935>] smpboot_thread_fn+0x105/0x160 [<ffffffff810a3830>] ? sort_range+0x30/0x30 [<ffffffff810a0588>] kthread+0xd8/0xf0 [<ffffffff810a04b0>] ? kthread_create_on_node+0x1e0/0x1e0 [<ffffffff8182568f>] ret_from_fork+0x3f/0x70 [<ffffffff810a04b0>] ? kthread_create_on_node+0x1e0/0x1e0 Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xen/events: Mask a moving irqBoris Ostrovsky2016-05-011-4/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit ff1e22e7a638a0782f54f81a6c9cb139aca2da35 upstream. Moving an unmasked irq may result in irq handler being invoked on both source and target CPUs. With 2-level this can happen as follows: On source CPU: evtchn_2l_handle_events() -> generic_handle_irq() -> handle_edge_irq() -> eoi_pirq(): irq_move_irq(data); /***** WE ARE HERE *****/ if (VALID_EVTCHN(evtchn)) clear_evtchn(evtchn); If at this moment target processor is handling an unrelated event in evtchn_2l_handle_events()'s loop it may pick up our event since target's cpu_evtchn_mask claims that this event belongs to it *and* the event is unmasked and still pending. At the same time, source CPU will continue executing its own handle_edge_irq(). With FIFO interrupt the scenario is similar: irq_move_irq() may result in a EVTCHNOP_unmask hypercall which, in turn, may make the event pending on the target CPU. We can avoid this situation by moving and clearing the event while keeping event masked. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xen/pciback: Save the number of MSI-X entries to be copied later.Konrad Rzeszutek Wilk2016-03-081-1/+5
| | | | | | | | | | | | | | | | | | commit d159457b84395927b5a52adb72f748dd089ad5e5 upstream. Commit 8135cf8b092723dbfcc611fe6fdcb3a36c9951c5 (xen/pciback: Save xen_pci_op commands before processing it) broke enabling MSI-X because it would never copy the resulting vectors into the response. The number of vectors requested was being overwritten by the return value (typically zero for success). Save the number of vectors before processing the op, so the correct number of vectors are copied afterwards. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/pciback: Check PF instead of VF for PCI_COMMAND_MEMORYKonrad Rzeszutek Wilk2016-03-081-1/+2
| | | | | | | | | | | | | | | | commit 8d47065f7d1980dde52abb874b301054f3013602 upstream. Commit 408fb0e5aa7fda0059db282ff58c3b2a4278baa0 (xen/pciback: Don't allow MSI-X ops if PCI_COMMAND_MEMORY is not set) prevented enabling MSI-X on passed-through virtual functions, because it checked the VF for PCI_COMMAND_MEMORY but this is not a valid bit for VFs. Instead, check the physical function for PCI_COMMAND_MEMORY. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/pciback: Don't allow MSI-X ops if PCI_COMMAND_MEMORY is not set.Konrad Rzeszutek Wilk2016-01-251-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 408fb0e5aa7fda0059db282ff58c3b2a4278baa0 upstream. commit f598282f51 ("PCI: Fix the NIU MSI-X problem in a better way") teaches us that dealing with MSI-X can be troublesome. Further checks in the MSI-X architecture shows that if the PCI_COMMAND_MEMORY bit is turned of in the PCI_COMMAND we may not be able to access the BAR (since they are memory regions). Since the MSI-X tables are located in there.. that can lead to us causing PCIe errors. Inhibit us performing any operation on the MSI-X unless the MEMORY bit is set. Note that Xen hypervisor with: "x86/MSI-X: access MSI-X table only after having enabled MSI-X" will return: xen_pciback: 0000:0a:00.1: error -6 enabling MSI-X for guest 3! When the generic MSI code tries to setup the PIRQ without MEMORY bit set. Which means with later versions of Xen (4.6) this patch is not neccessary. This is part of XSA-157 Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/pciback: For XEN_PCI_OP_disable_msi[|x] only disable if device has ↵Konrad Rzeszutek Wilk2016-01-251-13/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | MSI(X) enabled. commit 7cfb905b9638982862f0331b36ccaaca5d383b49 upstream. Otherwise just continue on, returning the same values as previously (return of 0, and op->result has the PIRQ value). This does not change the behavior of XEN_PCI_OP_disable_msi[|x]. The pci_disable_msi or pci_disable_msix have the checks for msi_enabled or msix_enabled so they will error out immediately. However the guest can still call these operations and cause us to disable the 'ack_intr'. That means the backend IRQ handler for the legacy interrupt will not respond to interrupts anymore. This will lead to (if the device is causing an interrupt storm) for the Linux generic code to disable the interrupt line. Naturally this will only happen if the device in question is plugged in on the motherboard on shared level interrupt GSI. This is part of XSA-157 Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/pciback: Do not install an IRQ handler for MSI interrupts.Konrad Rzeszutek Wilk2016-01-251-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit a396f3a210c3a61e94d6b87ec05a75d0be2a60d0 upstream. Otherwise an guest can subvert the generic MSI code to trigger an BUG_ON condition during MSI interrupt freeing: for (i = 0; i < entry->nvec_used; i++) BUG_ON(irq_has_action(entry->irq + i)); Xen PCI backed installs an IRQ handler (request_irq) for the dev->irq whenever the guest writes PCI_COMMAND_MEMORY (or PCI_COMMAND_IO) to the PCI_COMMAND register. This is done in case the device has legacy interrupts the GSI line is shared by the backend devices. To subvert the backend the guest needs to make the backend to change the dev->irq from the GSI to the MSI interrupt line, make the backend allocate an interrupt handler, and then command the backend to free the MSI interrupt and hit the BUG_ON. Since the backend only calls 'request_irq' when the guest writes to the PCI_COMMAND register the guest needs to call XEN_PCI_OP_enable_msi before any other operation. This will cause the generic MSI code to setup an MSI entry and populate dev->irq with the new PIRQ value. Then the guest can write to PCI_COMMAND PCI_COMMAND_MEMORY and cause the backend to setup an IRQ handler for dev->irq (which instead of the GSI value has the MSI pirq). See 'xen_pcibk_control_isr'. Then the guest disables the MSI: XEN_PCI_OP_disable_msi which ends up triggering the BUG_ON condition in 'free_msi_irqs' as there is an IRQ handler for the entry->irq (dev->irq). Note that this cannot be done using MSI-X as the generic code does not over-write dev->irq with the MSI-X PIRQ values. The patch inhibits setting up the IRQ handler if MSI or MSI-X (for symmetry reasons) code had been called successfully. P.S. Xen PCIBack when it sets up the device for the guest consumption ends up writting 0 to the PCI_COMMAND (see xen_pcibk_reset_device). XSA-120 addendum patch removed that - however when upstreaming said addendum we found that it caused issues with qemu upstream. That has now been fixed in qemu upstream. This is part of XSA-157 Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/pciback: Return error on XEN_PCI_OP_enable_msix when device has MSI or ↵Konrad Rzeszutek Wilk2016-01-251-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | MSI-X enabled commit 5e0ce1455c09dd61d029b8ad45d82e1ac0b6c4c9 upstream. The guest sequence of: a) XEN_PCI_OP_enable_msix b) XEN_PCI_OP_enable_msix results in hitting an NULL pointer due to using freed pointers. The device passed in the guest MUST have MSI-X capability. The a) constructs and SysFS representation of MSI and MSI groups. The b) adds a second set of them but adding in to SysFS fails (duplicate entry). 'populate_msi_sysfs' frees the newly allocated msi_irq_groups (note that in a) pdev->msi_irq_groups is still set) and also free's ALL of the MSI-X entries of the device (the ones allocated in step a) and b)). The unwind code: 'free_msi_irqs' deletes all the entries and tries to delete the pdev->msi_irq_groups (which hasn't been set to NULL). However the pointers in the SysFS are already freed and we hit an NULL pointer further on when 'strlen' is attempted on a freed pointer. The patch adds a simple check in the XEN_PCI_OP_enable_msix to guard against that. The check for msi_enabled is not stricly neccessary. This is part of XSA-157 Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/pciback: Return error on XEN_PCI_OP_enable_msi when device has MSI or ↵Konrad Rzeszutek Wilk2016-01-251-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | MSI-X enabled commit 56441f3c8e5bd45aab10dd9f8c505dd4bec03b0d upstream. The guest sequence of: a) XEN_PCI_OP_enable_msi b) XEN_PCI_OP_enable_msi c) XEN_PCI_OP_disable_msi results in hitting an BUG_ON condition in the msi.c code. The MSI code uses an dev->msi_list to which it adds MSI entries. Under the above conditions an BUG_ON() can be hit. The device passed in the guest MUST have MSI capability. The a) adds the entry to the dev->msi_list and sets msi_enabled. The b) adds a second entry but adding in to SysFS fails (duplicate entry) and deletes all of the entries from msi_list and returns (with msi_enabled is still set). c) pci_disable_msi passes the msi_enabled checks and hits: BUG_ON(list_empty(dev_to_msi_list(&dev->dev))); and blows up. The patch adds a simple check in the XEN_PCI_OP_enable_msi to guard against that. The check for msix_enabled is not stricly neccessary. This is part of XSA-157. Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/pciback: Save xen_pci_op commands before processing itKonrad Rzeszutek Wilk2016-01-252-1/+15
| | | | | | | | | | | | | | | | | | | | | | | | | commit 8135cf8b092723dbfcc611fe6fdcb3a36c9951c5 upstream. Double fetch vulnerabilities that happen when a variable is fetched twice from shared memory but a security check is only performed the first time. The xen_pcibk_do_op function performs a switch statements on the op->cmd value which is stored in shared memory. Interestingly this can result in a double fetch vulnerability depending on the performed compiler optimization. This patch fixes it by saving the xen_pci_op command before processing it. We also use 'barrier' to make sure that the compiler does not perform any optimization. This is part of XSA155. Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Jan Beulich <JBeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/events/fifo: Consume unprocessed events when a CPU diesRoss Lagerwall2016-01-251-5/+18
| | | | | | | | | | | | | | | commit 3de88d622fd68bd4dbee0f80168218b23f798fd0 upstream. When a CPU is offlined, there may be unprocessed events on a port for that CPU. If the port is subsequently reused on a different CPU, it could be in an unexpected state with the link bit set, resulting in interrupts being missed. Fix this by consuming any unprocessed events for a particular CPU when that CPU dies. Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> [ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/gntdev: Grant maps should not be subject to NUMA balancingBoris Ostrovsky2015-12-181-1/+1
| | | | | | | | | | | | | | | | | | | | commit 9c17d96500f78d7ecdb71ca6942830158bc75a2b upstream. Doing so will cause the grant to be unmapped and then, during fault handling, the fault to be mistakenly treated as NUMA hint fault. In addition, even if those maps could partcipate in NUMA balancing, it wouldn't provide any benefit since we are unable to determine physical page's node (even if/when VNUMA is implemented). Marking grant maps' VMAs as VM_IO will exclude them from being part of NUMA balancing. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/gntdevt: Fix race condition in gntdev_release()Marek Marczykowski-Górecki2015-09-031-0/+2
| | | | | | | | | | | | | | | commit 30b03d05e07467b8c6ec683ea96b5bffcbcd3931 upstream. While gntdev_release() is called the MMU notifier is still registered and can traverse priv->maps list even if no pages are mapped (which is the case -- gntdev_release() is called after all). But gntdev_release() will clear that list, so make sure that only one of those things happens at the same time. Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/gntdev: convert priv->lock to a mutexDavid Vrabel2015-09-031-20/+20
| | | | | | | | | | | | | | commit 1401c00e59ea021c575f74612fe2dbba36d6a4ee upstream. Unmapping may require sleeping and we unmap while holding priv->lock, so convert it to a mutex. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> [ luis: 3.16 prereq for: 30b03d05e074 xen/gntdevt: Fix race condition in gntdev_release() ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/events: don't bind non-percpu VIRQs with percpu chipDavid Vrabel2015-06-021-4/+8
| | | | | | | | | | | | | | | | | | | | | | | | commit 77bb3dfdc0d554befad58fdefbc41be5bc3ed38a upstream. A non-percpu VIRQ (e.g., VIRQ_CONSOLE) may be freed on a different VCPU than it is bound to. This can result in a race between handle_percpu_irq() and removing the action in __free_irq() because handle_percpu_irq() does not take desc->lock. The interrupt handler sees a NULL action and oopses. Only use the percpu chip/handler for per-CPU VIRQs (like VIRQ_TIMER). # cat /proc/interrupts | grep virq 40: 87246 0 xen-percpu-virq timer0 44: 0 0 xen-percpu-virq debug0 47: 0 20995 xen-percpu-virq timer1 51: 0 0 xen-percpu-virq debug1 69: 0 0 xen-dyn-virq xen-pcpu 74: 0 0 xen-dyn-virq mce 75: 29 0 xen-dyn-virq hvc_console Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen-pciback: Add name prefix to global 'permissive' variableBen Hutchings2015-05-203-5/+5
| | | | | | | | | | | | | | commit 8014bcc86ef112eab9ee1db312dba4e6b608cf89 upstream. The variable for the 'permissive' module parameter used to be static but was recently changed to be extern. This puts it in the kernel global namespace if the driver is built-in, so its name should begin with a prefix identifying the driver. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Fixes: af6fc858a35b ("xen-pciback: limit guest control of command register") Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/events: Set irq_info->evtchn before binding the channel to CPU in ↵Boris Ostrovsky2015-05-201-1/+1
| | | | | | | | | | | | | | __startup_pirq() commit 16e6bd5970c88a2ac018b84a5f1dd5c2ff1fdf2c upstream. .. because bind_evtchn_to_cpu(evtchn, cpu) will map evtchn to 'info' and pass 'info' down to xen_evtchn_port_bind_to_cpu(). Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Tested-by: Annie Li <annie.li@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/xenbus: Update xenbus event channel on resumeBoris Ostrovsky2015-05-201-0/+29
| | | | | | | | | | | commit 16f1cf3ba7303228372d3756677bf7d10e79cf9f upstream. After a resume the hypervisor/tools may change xenbus event channel number. We should re-query it. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/events: Clear cpu_evtchn_mask before resumingBoris Ostrovsky2015-05-202-2/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 5cec98834989a014a9560b1841649eaca95cf00e upstream. When a guest is resumed, the hypervisor may change event channel assignments. If this happens and the guest uses 2-level events it is possible for the interrupt to be claimed by wrong VCPU since cpu_evtchn_mask bits may be stale. This can happen even though evtchn_2l_bind_to_cpu() attempts to clear old bits: irq_info that is passed in is not necessarily the original one (from pre-migration times) but instead is freshly allocated during resume and so any information about which CPU the channel was bound to is lost. Thus we should clear the mask during resume. We also need to make sure that bits for xenstore and console channels are set when these two subsystems are resumed. While rebind_evtchn_irq() (which is invoked for both of them on a resume) calls irq_set_affinity(), the latter will in fact postpone setting affinity until handling the interrupt. But because cpu_evtchn_mask will have bits for these two cleared we won't be able to take the interrupt. With that in mind, we need to bind those two channels explicitly in rebind_evtchn_irq(). We will keep irq_set_affinity() so that we have a pass through generic irq affinity code later, in case something needs to be updated there as well. (Also replace cpumask_of(0) with cpumask_of(info->cpu) in rebind_evtchn_irq(): it should be set to zero in preceding xen_irq_info_evtchn_setup().) Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reported-by: Annie Li <annie.li@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/balloon: before adding hotplugged memory, set frames to invalidJuergen Gross2015-04-131-0/+23
| | | | | | | | | | | | | | | | | commit 3c56b3a12ce52f361468cbdd2f79b2f3b8da0ea6 upstream. Commit 25b884a83d487fd62c3de7ac1ab5549979188482 ("x86/xen: set regions above the end of RAM as 1:1") introduced a regression. To be able to add memory pages which were added via memory hotplug to a pv domain, the pages must be "invalid" instead of "identity" in the p2m list before they can be added. Suggested-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen-pciback: limit guest control of command registerJan Beulich2015-03-233-14/+51
| | | | | | | | | | | | | | | | | | | | | commit af6fc858a35b90e89ea7a7ee58e66628c55c776b upstream. Otherwise the guest can abuse that control to cause e.g. PCIe Unsupported Request responses by disabling memory and/or I/O decoding and subsequently causing (CPU side) accesses to the respective address ranges, which (depending on system configuration) may be fatal to the host. Note that to alter any of the bits collected together as PCI_COMMAND_GUEST permissive mode is now required to be enabled globally or on the specific device. This is CVE-2015-2150 / XSA-120. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/events: avoid NULL pointer dereference in dom0 on large machinesJuergen Gross2015-03-231-6/+12
| | | | | | | | | | | | | | | | | | | | | commit 85e40b0539b24518c8bdf63e2605c8522377d00f upstream. Using the pvops kernel a NULL pointer dereference was detected on a large machine (144 processors) when booting as dom0 in evtchn_fifo_unmask() during assignment of a pirq. The event channel in question was the first to need a new entry in event_array[] in events_fifo.c. Unfortunately xen_irq_info_pirq_setup() is called with evtchn being 0 for a new pirq and the real event channel number is assigned to the pirq only during __startup_pirq(). It is mandatory to call xen_evtchn_port_setup() after assigning the event channel number to the pirq to make sure all memory needed for the event channel is allocated. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/manage: Fix USB interaction issues when resumingRoss Lagerwall2015-03-021-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 72978b2fe2f2cdf9f319c6c6dcdbe92b38de2be2 upstream. Commit 61a734d305e1 ("xen/manage: Always freeze/thaw processes when suspend/resuming") ensured that userspace processes were always frozen before suspending to reduce interaction issues when resuming devices. However, freeze_processes() does not freeze kernel threads. Freeze kernel threads as well to prevent deadlocks with the khubd thread when resuming devices. This is what native suspend and resume does. Example deadlock: [ 7279.648010] [<ffffffff81446bde>] ? xen_poll_irq_timeout+0x3e/0x50 [ 7279.648010] [<ffffffff81448d60>] xen_poll_irq+0x10/0x20 [ 7279.648010] [<ffffffff81011723>] xen_lock_spinning+0xb3/0x120 [ 7279.648010] [<ffffffff810115d1>] __raw_callee_save_xen_lock_spinning+0x11/0x20 [ 7279.648010] [<ffffffff815620b6>] ? usb_control_msg+0xe6/0x120 [ 7279.648010] [<ffffffff81747e50>] ? _raw_spin_lock_irq+0x50/0x60 [ 7279.648010] [<ffffffff8174522c>] wait_for_completion+0xac/0x160 [ 7279.648010] [<ffffffff8109c520>] ? try_to_wake_up+0x2c0/0x2c0 [ 7279.648010] [<ffffffff814b60f2>] dpm_wait+0x32/0x40 [ 7279.648010] [<ffffffff814b6eb0>] device_resume+0x90/0x210 [ 7279.648010] [<ffffffff814b7d71>] dpm_resume+0x121/0x250 [ 7279.648010] [<ffffffff8144c570>] ? xenbus_dev_request_and_reply+0xc0/0xc0 [ 7279.648010] [<ffffffff814b80d5>] dpm_resume_end+0x15/0x30 [ 7279.648010] [<ffffffff81449fba>] do_suspend+0x10a/0x200 [ 7279.648010] [<ffffffff8144a2f0>] ? xen_pre_suspend+0x20/0x20 [ 7279.648010] [<ffffffff8144a1d0>] shutdown_handler+0x120/0x150 [ 7279.648010] [<ffffffff8144c60f>] xenwatch_thread+0x9f/0x160 [ 7279.648010] [<ffffffff810ac510>] ? finish_wait+0x80/0x80 [ 7279.648010] [<ffffffff8108d189>] kthread+0xc9/0xe0 [ 7279.648010] [<ffffffff8108d0c0>] ? flush_kthread_worker+0x80/0x80 [ 7279.648010] [<ffffffff8175087c>] ret_from_fork+0x7c/0xb0 [ 7279.648010] [<ffffffff8108d0c0>] ? flush_kthread_worker+0x80/0x80 [ 7441.216287] INFO: task khubd:89 blocked for more than 120 seconds. [ 7441.219457] Tainted: G X 3.13.11-ckt12.kz #1 [ 7441.222176] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 7441.225827] khubd D ffff88003f433440 0 89 2 0x00000000 [ 7441.229258] ffff88003ceb9b98 0000000000000046 ffff88003ce83000 0000000000013440 [ 7441.232959] ffff88003ceb9fd8 0000000000013440 ffff88003cd13000 ffff88003ce83000 [ 7441.236658] 0000000000000286 ffff88003d3e0000 ffff88003ceb9bd0 00000001001aa01e [ 7441.240415] Call Trace: [ 7441.241614] [<ffffffff817442f9>] schedule+0x29/0x70 [ 7441.243930] [<ffffffff81743406>] schedule_timeout+0x166/0x2c0 [ 7441.246681] [<ffffffff81075b80>] ? call_timer_fn+0x110/0x110 [ 7441.249339] [<ffffffff8174357e>] schedule_timeout_uninterruptible+0x1e/0x20 [ 7441.252644] [<ffffffff81077710>] msleep+0x20/0x30 [ 7441.254812] [<ffffffff81555f00>] hub_port_reset+0xf0/0x580 [ 7441.257400] [<ffffffff81558465>] hub_port_init+0x75/0xb40 [ 7441.259981] [<ffffffff814bb3c9>] ? update_autosuspend+0x39/0x60 [ 7441.262817] [<ffffffff814bb4f0>] ? pm_runtime_set_autosuspend_delay+0x50/0xa0 [ 7441.266212] [<ffffffff8155a64a>] hub_thread+0x71a/0x1750 [ 7441.268728] [<ffffffff810ac510>] ? finish_wait+0x80/0x80 [ 7441.271272] [<ffffffff81559f30>] ? usb_port_resume+0x670/0x670 [ 7441.274067] [<ffffffff8108d189>] kthread+0xc9/0xe0 [ 7441.276305] [<ffffffff8108d0c0>] ? flush_kthread_worker+0x80/0x80 [ 7441.279131] [<ffffffff8175087c>] ret_from_fork+0x7c/0xb0 [ 7441.281659] [<ffffffff8108d0c0>] ? flush_kthread_worker+0x80/0x80 Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* Revert "swiotlb-xen: pass dev_addr to swiotlb_tbl_unmap_single"David Vrabel2015-01-261-1/+1
| | | | | | | | | | | | | | | commit dbdd74763f1faf799fbb9ed30423182e92919378 upstream. This reverts commit 2c3fc8d26dd09b9d7069687eead849ee81c78e46. This commit broke on x86 PV because entries in the generic SWIOTLB are indexed using (pseudo-)physical address not DMA address and these are not the same in a x86 PV guest. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/arm/arm64: introduce xen_arch_need_swiotlbStefano Stabellini2015-01-161-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit a4dba130891271084344c12537731542ec77cb85 upstream. Introduce an arch specific function to find out whether a particular dma mapping operation needs to bounce on the swiotlb buffer. On ARM and ARM64, if the page involved is a foreign page and the device is not coherent, we need to bounce because at unmap time we cannot execute any required cache maintenance operations (we don't know how to find the pfn from the mfn). No change of behaviour for x86. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [ stefano: The commit needs to be slightly modified because is_device_dma_coherent is not available on kernels < 3.19, so I just removed the call, thus assuming that the device is not coherent on arm (slower but safe) ] Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> [ luis: backported to 3.16: used backport by stefano ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* swiotlb-xen: pass dev_addr to swiotlb_tbl_unmap_singleStefano Stabellini2015-01-151-1/+1
| | | | | | | | | | | | commit 2c3fc8d26dd09b9d7069687eead849ee81c78e46 upstream. Need to pass the pointer within the swiotlb internal buffer to the swiotlb library, that in the case of xen_unmap_single is dev_addr, not paddr. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* swiotlb-xen: call xen_dma_sync_single_for_device when appropriateStefano Stabellini2015-01-151-1/+1
| | | | | | | | | | | commit 9490c6c67e2f41760de8ece4e4f56f75f84ceb9e upstream. In xen_swiotlb_sync_single we always call xen_dma_sync_single_for_cpu, even when we should call xen_dma_sync_single_for_device. Fix that. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* swiotlb-xen: remove BUG_ON in xen_bus_to_physStefano Stabellini2015-01-151-2/+0
| | | | | | | | | | | | | | | | | commit c884227eaae9936f8ecbde6e1387bccdab5f4e90 upstream. On x86 truncation cannot occur because config XEN depends on X86_64 || (X86_32 && X86_PAE). On ARM truncation can occur without CONFIG_ARM_LPAE, when the dma operation involves foreign grants. However in that case the physical address returned by xen_bus_to_phys is actually invalid (there is no mfn to pfn tracking for foreign grants on ARM) and it is not used. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* swiotlb-xen: pass dev_addr to xen_dma_unmap_page and xen_dma_sync_single_for_cpuStefano Stabellini2015-01-151-3/+3
| | | | | | | | | | | | commit d6883e6f32e07ef2cc974753ba00927de099e6d7 upstream. xen_dma_unmap_page and xen_dma_sync_single_for_cpu take a dma_addr_t handle as argument, not a physical address. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
* xen/manage: Always freeze/thaw processes when suspend/resumingRoss Lagerwall2014-10-051-7/+0
| | | | | | | | | | | | | | | | | | | | | commit 61a734d305e16944b42730ef582a7171dc733321 upstream. Always freeze processes when suspending and thaw processes when resuming to prevent a race noticeable with HVM guests. This prevents a deadlock where the khubd kthread (which is designed to be freezable) acquires a usb device lock and then tries to allocate memory which requires the disk which hasn't been resumed yet. Meanwhile, the xenwatch thread deadlocks waiting for the usb device lock. Freezing processes fixes this because the khubd thread is only thawed after the xenwatch thread finishes resuming all the devices. Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xen/events/fifo: reset control block and local HEADs on resumeDavid Vrabel2014-09-171-20/+28
| | | | | | | | | | | | | | | | commit c12784c3d14a2110468ec4d1383f60cfd2665576 upstream. When using the FIFO-based event channel ABI, if the control block or the local HEADs are not reset after resuming the guest may see stale HEAD values and will fail to traverse the FIFO correctly. This may prevent one or more VCPUs from receiving any events following a resume. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xen/events/fifo: ensure all bitops are properly aligned even on x86David Vrabel2014-09-051-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | commit dcecb8fd93a65787130a74e61fdf29932c8d85eb upstream. When using the FIFO-based ABI on x86_64, if the last port is at the end of an event array page then sync_test_bit() on this port's event word will read beyond the end of the page and in certain circumstances this may fault. The fault requires the following page in the kernel's direct mapping to be not present, which would mean: a) the array page is the last page of RAM; or b) the following page is ballooned out /and/ it has been used for a foreign mapping by a kernel driver (such as netback or blkback) /and/ the grant has been unmapped. Use the infrastructure added for arm64 to ensure that all bitops operating on event words are unsigned long aligned. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'stable/for-linus-3.16-rc7-tag' of ↵Linus Torvalds2014-07-301-1/+8
|\ | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen fix from David Vrabel: "Fix BUG when trying to expand the grant table. This seems to occur often during boot with Ubuntu 14.04 PV guests" * tag 'stable/for-linus-3.16-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86/xen: safely map and unmap grant frames when in atomic context
| * x86/xen: safely map and unmap grant frames when in atomic contextDavid Vrabel2014-07-301-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | arch_gnttab_map_frames() and arch_gnttab_unmap_frames() are called in atomic context but were calling alloc_vm_area() which might sleep. Also, if a driver attempts to allocate a grant ref from an interrupt and the table needs expanding, then the CPU may already by in lazy MMU mode and apply_to_page_range() will BUG when it tries to re-enable lazy MMU mode. These two functions are only used in PV guests. Introduce arch_gnttab_init() to allocates the virtual address space in advance. Avoid the use of apply_to_page_range() by using saving and using the array of PTE addresses from the alloc_vm_area() call (which ensures that the required page tables are pre-allocated). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | Merge tag 'stable/for-linus-3.16-rc5-tag' of ↵Linus Torvalds2014-07-172-8/+9
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen fixes from Konrad Rzeszutek Wilk: "Two fixes found during migration of PV guests. David would be the one doing this pull but he is on vacation. Fixes: - fix console deadlock when resuming PV guests - fix regression hit when ballooning and resuming PV guests" * tag 'stable/for-linus-3.16-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/balloon: set ballooned out pages as invalid in p2m xen/manage: fix potential deadlock when resuming the console
| * xen/balloon: set ballooned out pages as invalid in p2mDavid Vrabel2014-07-041-7/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since cd9151e26d31048b2b5e00fd02e110e07d2200c9 (xen/balloon: set a mapping for ballooned out pages), a ballooned out page had its entry in the p2m set to the MFN of one of the scratch pages. This means that the p2m will contain many entries pointing to the same MFN. During a domain save, these many-to-one entries are not identified as such and the scratch page is saved multiple times. On restore the ballooned pages are populated with new frames and the domain may use up its allocation before all pages can be restored. Since the original fix only needed to keep a mapping for the ballooned page it is safe to set ballooned out pages as INVALID_P2M_ENTRY in the p2m (as they were before). Thus preventing them from being saved and re-populated on restore. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reported-by: Marek Marczykowski <marmarek@invisiblethingslab.com> Tested-by: Marek Marczykowski <marmarek@invisiblethingslab.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: <stable@vger.kernel.org>
| * xen/manage: fix potential deadlock when resuming the consoleDavid Vrabel2014-07-031-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Calling xen_console_resume() in xen_suspend() causes a warning because it locks irq_mapping_update_lock (a mutex) and this may sleep. If a userspace process is using the evtchn device then this mutex may be locked at the point of the stop_machine() call and xen_console_resume() would then deadlock. Resuming the console after stop_machine() returns avoids this deadlock. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: <stable@vger.kernel.org>
* | Merge tag 'stable/for-linus-3.16-rc1-tag' of ↵Linus Torvalds2014-06-191-1/+2
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen fixes from David Vrabel: "Xen regression and PVH fixes for 3.16-rc1 - fix dom0 PVH memory setup on latest unstable Xen releases - fix 64-bit x86 PV guest boot failure on Xen 3.1 and earlier - fix resume regression on non-PV (auto-translated physmap) guests" * tag 'stable/for-linus-3.16-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/grant-table: fix suspend for non-PV guests x86/xen: no need to explicitly register an NMI callback Revert "xen/pvh: Update E820 to work with PVH (v2)" x86/xen: fix memory setup for PVH dom0
| * xen/grant-table: fix suspend for non-PV guestsDavid Vrabel2014-06-181-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | Commit aa8532c32216ae07c3813b9aeb774517878a7573 (xen: refactor suspend pre/post hooks) broke resuming PVHVM (auto-translated physmap) guests. The gnttab_suspend() would clear the mapping for the grant table frames, but the ->unmap_frames() call is only applicable to PV guests. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>