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2017-02-09xen: modify xenstore watch event interfaceJuergen Gross1-1/+1
Today a Xenstore watch event is delivered via a callback function declared as: void (*callback)(struct xenbus_watch *, const char **vec, unsigned int len); As all watch events only ever come with two parameters (path and token) changing the prototype to: void (*callback)(struct xenbus_watch *, const char *path, const char *token); is the natural thing to do. Apply this change and adapt all users. Cc: konrad.wilk@oracle.com Cc: roger.pau@citrix.com Cc: wei.liu2@citrix.com Cc: paul.durrant@citrix.com Cc: netdev@vger.kernel.org Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Paul Durrant <paul.durrant@citrix.com> Reviewed-by: Wei Liu <wei.liu2@citrix.com> Reviewed-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2016-11-07xen: make use of xenbus_read_unsigned() in xen-pcibackJuergen Gross1-5/+3
Use xenbus_read_unsigned() instead of xenbus_scanf() when possible. This requires to change the type of the read from int to unsigned, but this case has been wrong before: negative values are not allowed for the modified case. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: David Vrabel <david.vrabel@citrix.com>
2016-09-30xen/pciback: support driver_overrideJuergen Gross1-7/+29
Support the driver_override scheme introduced with commit 782a985d7af2 ("PCI: Introduce new device binding path using pci_dev.driver_override") As pcistub_probe() is called for all devices (it has to check for a match based on the slot address rather than device type) it has to check for driver_override set to "pciback" itself. Up to now for assigning a pci device to pciback you need something like: echo 0000:07:10.0 > /sys/bus/pci/devices/0000\:07\:10.0/driver/unbind echo 0000:07:10.0 > /sys/bus/pci/drivers/pciback/new_slot echo 0000:07:10.0 > /sys/bus/pci/drivers_probe while with the patch you can use the same mechanism as for similar drivers like pci-stub and vfio-pci: echo pciback > /sys/bus/pci/devices/0000\:07\:10.0/driver_override echo 0000:07:10.0 > /sys/bus/pci/devices/0000\:07\:10.0/driver/unbind echo 0000:07:10.0 > /sys/bus/pci/drivers_probe So e.g. libvirt doesn't need special handling for pciback. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-09-30xen/pciback: avoid multiple entries in slot listJuergen Gross1-8/+31
The Xen pciback driver has a list of all pci devices it is ready to seize. There is no check whether a to be added entry already exists. While this might be no problem in the common case it might confuse those which consume the list via sysfs. Modify the handling of this list by not adding an entry which already exists. As this will be needed later split out the list handling into a separate function. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-09-30xen/pciback: simplify pcistub device handlingJuergen Gross1-21/+21
The Xen pciback driver maintains a list of all its seized devices. There are two functions searching the list for a specific device with basically the same semantics just returning different structures in case of a match. Split out the search function. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-06xen-pciback: drop superfluous variablesJan Beulich1-10/+6
req_start is simply an alias of the "offset" function parameter, and req_end is being used just once in each function. (And both variables were loop invariant anyway, so should at least have got initialized outside the loop.) Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-06xen-pciback: short-circuit read path used for merging write valuesJan Beulich1-4/+2
There's no point calling xen_pcibk_config_read() here - all it'll do is return whatever conf_space_read() returns for the field which was found here (and which would be found there again). Also there's no point clearing tmp_val before the call. Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-06xen-pciback: use const and unsigned in bar_init()Jan Beulich1-2/+2
Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-06xen-pciback: simplify determination of 64-bit memory resourceJan Beulich1-4/+1
Other than for raw BAR values, flags are properly separated in the internal representation. Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-06xen-pciback: fold read_dev_bar() into its now single callerJan Beulich1-20/+13
Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-06xen-pciback: drop rom_init()Jan Beulich1-13/+1
It is now identical to bar_init(). Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-06xen-pciback: drop unused function parameter of read_dev_bar()Jan Beulich1-4/+3
Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-06xen: xen-pciback: Remove create_workqueueBhaktipriya Shridhar3-11/+2
System workqueues have been able to handle high level of concurrency for a long time now and there's no reason to use dedicated workqueues just to gain concurrency. Replace dedicated xen_pcibk_wq with the use of system_wq. Unlike a dedicated per-cpu workqueue created with create_workqueue(), system_wq allows multiple work items to overlap executions even on the same CPU; however, a per-cpu workqueue doesn't have any CPU locality or global ordering guarantees unless the target CPU is explicitly specified and thus the increase of local concurrency shouldn't make any difference. Since the work items could be pending, flush_work() has been used in xen_pcibk_disconnect(). xen_pcibk_xenbus_remove() calls free_pdev() which in turn calls xen_pcibk_disconnect() for every pdev to ensure that there is no pending task while disconnecting the driver. Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-06-24xen-pciback: return proper values during BAR sizingJan Beulich1-7/+11
Reads following writes with all address bits set to 1 should return all changeable address bits as one, not the BAR size (nor, as was the case for the upper half of 64-bit BARs, the high half of the region's end address). Presumably this didn't cause any problems so far because consumers use the value to calculate the size (usually via val & -val), and do nothing else with it. But also consider the exception here: Unimplemented BARs should always return all zeroes. And finally, the check for whether to return the sizing address on read for the ROM BAR should ignore all non-address bits, not just the ROM Enable one. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-06-23xen/pciback: Fix conf_space read/write overlap check.Andrey Grodzovsky1-4/+2
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> Cc: <stable@vger.kernel.org> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-03-22Merge tag 'for-linus-4.6-rc0-tag' of ↵Linus Torvalds3-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from David Vrabel: "Features and fixes for 4.6: - Make earlyprintk=xen work for HVM guests - Remove module support for things never built as modules" * tag 'for-linus-4.6-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: drivers/xen: make platform-pci.c explicitly non-modular drivers/xen: make sys-hypervisor.c explicitly non-modular drivers/xen: make xenbus_dev_[front/back]end explicitly non-modular drivers/xen: make [xen-]ballon explicitly non-modular xen: audit usages of module.h ; remove unnecessary instances xen/x86: Drop mode-selecting ifdefs in startup_xen() xen/x86: Zero out .bss for PV guests hvc_xen: make early_printk work with HVM guests hvc_xen: fix xenboot for DomUs hvc_xen: add earlycon support
2016-03-21xen: audit usages of module.h ; remove unnecessary instancesPaul Gortmaker3-3/+3
Code that uses no modular facilities whatsoever should not be sourcing module.h at all, since that header drags in a bunch of other headers with it. Similarly, code that is not explicitly using modular facilities like module_init() but only is declaring module_param setup variables should be using moduleparam.h and not the larger module.h file for that. In making this change, we also uncover an implicit use of BUG() in inline fcns within arch/arm/include/asm/xen/hypercall.h so we explicitly source <linux/bug.h> for that file now. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-02-15xen/pciback: Save the number of MSI-X entries to be copied later.Konrad Rzeszutek Wilk1-1/+5
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> Cc: <stable@vger.kernel.org> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-02-15xen/pciback: Check PF instead of VF for PCI_COMMAND_MEMORYKonrad Rzeszutek Wilk1-1/+2
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> Cc: <stable@vger.kernel.org> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-12-18xen-pciback: fix up cleanup path when alloc failsDoug Goldstein1-1/+3
When allocating a pciback device fails, clear the private field. This could lead to an use-after free, however the 'really_probe' takes care of setting dev_set_drvdata(dev, NULL) in its failure path (which we would exercise if the ->probe function failed), so we we are OK. However lets be defensive as the code can change. Going forward we should clean up the pci_set_drvdata(dev, NULL) in the various code-base. That will be for another day. Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reported-by: Jonathan Creekmore <jonathan.creekmore@gmail.com> Signed-off-by: Doug Goldstein <cardoe@cardoe.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2015-12-18xen/pciback: Don't allow MSI-X ops if PCI_COMMAND_MEMORY is not set.Konrad Rzeszutek Wilk1-1/+7
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 CC: stable@vger.kernel.org Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2015-12-18xen/pciback: For XEN_PCI_OP_disable_msi[|x] only disable if device has ↵Konrad Rzeszutek Wilk1-13/+20
MSI(X) enabled. 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 CC: stable@vger.kernel.org Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2015-12-18xen/pciback: Do not install an IRQ handler for MSI interrupts.Konrad Rzeszutek Wilk1-0/+7
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 CC: stable@vger.kernel.org Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2015-12-18xen/pciback: Return error on XEN_PCI_OP_enable_msix when device has MSI or ↵Konrad Rzeszutek Wilk1-0/+7
MSI-X enabled 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 CC: stable@vger.kernel.org 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>
2015-12-18xen/pciback: Return error on XEN_PCI_OP_enable_msi when device has MSI or ↵Konrad Rzeszutek Wilk1-1/+6
MSI-X enabled 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. CC: stable@vger.kernel.org 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>
2015-12-18xen/pciback: Save xen_pci_op commands before processing itKonrad Rzeszutek Wilk2-1/+15
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. CC: stable@vger.kernel.org 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>
2015-04-29xen-pciback: Add name prefix to global 'permissive' variableBen Hutchings3-5/+5
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>
2015-04-15xenbus_client: Extend interface to support multi-page ringWei Liu1-1/+1
Originally Xen PV drivers only use single-page ring to pass along information. This might limit the throughput between frontend and backend. The patch extends Xenbus driver to support multi-page ring, which in general should improve throughput if ring is the bottleneck. Changes to various frontend / backend to adapt to the new interface are also included. Affected Xen drivers: * blkfront/back * netfront/back * pcifront/back * scsifront/back * vtpmfront The interface is documented, as before, in xenbus_client.c. Signed-off-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Signed-off-by: Bob Liu <bob.liu@oracle.com> Cc: Konrad Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-03-16xen-pciback: also support disabling of bus-mastering and memory-write-invalidateJan Beulich1-1/+14
It's not clear to me why only the enabling operation got handled so far. 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>
2015-03-16xen/pciback: Don't print scary messages when unsupported by hypervisor.Konrad Rzeszutek Wilk1-2/+2
We print at the warninig level messages such as: pciback 0000:90:00.5: MSI-X preparation failed (-38) which is due to the hypervisor not supporting this sub-hypercall (which was added in Xen 4.3). Instead of having scary messages all the time - only have it when the hypercall is actually supported. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-03-11xen-pciback: limit guest control of command registerJan Beulich3-14/+51
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> Cc: <stable@vger.kernel.org> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-12-04xen-pciback: drop SR-IOV VFs when PF driver unloadsJan Beulich1-0/+54
When a PF driver unloads, it may find it necessary to leave the VFs around simply because of pciback having marked them as assigned to a guest. Utilize a suitable notification to let go of the VFs, thus allowing the PF to go back into the state it was before its driver loaded (which in particular allows the driver to be loaded again with it being able to create the VFs anew, but which also allows to then pass through the PF instead of the VFs). Don't do this however for any VFs currently in active use by a guest. Signed-off-by: Jan Beulich <jbeulich@suse.com> [v2: Removed the switch statement, moved it about] [v3: Redid it a bit differently] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-12-04xen/pciback: Restore configuration space when detaching from a guest.Konrad Rzeszutek Wilk1-2/+14
The commit "xen/pciback: Don't deadlock when unbinding." was using the version of pci_reset_function which would lock the device lock. That is no good as we can dead-lock. As such we swapped to using the lock-less version and requiring that the callers of 'pcistub_put_pci_dev' take the device lock. And as such this bug got exposed. Using the lock-less version is OK, except that we tried to use 'pci_restore_state' after the lock-less version of __pci_reset_function_locked - which won't work as 'state_saved' is set to false. Said 'state_saved' is a toggle boolean that is to be used by the sequence of a) pci_save_state/pci_restore_state or b) pci_load_and_free_saved_state/pci_restore_state. We don't want to use a) as the guest might have messed up the PCI configuration space and we want it to revert to the state when the PCI device was binded to us. Therefore we pick b) to restore the configuration space. We restore from our 'golden' version of PCI configuration space, when an: - Device is unbinded from pciback - Device is detached from a guest. Reported-by: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-12-04xen/pciback: Remove tons of dereferencesKonrad Rzeszutek Wilk1-9/+11
A little cleanup. No functional difference. Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-12-04xen/pciback: Print out the domain owning the device.Konrad Rzeszutek Wilk1-1/+1
We had been printing it only if the device was built with debug enabled. But this information is useful in the field to troubleshoot. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-12-04xen/pciback: Include the domain id if removing the device whilst still in useKonrad Rzeszutek Wilk1-4/+6
Cleanup the function a bit - also include the id of the domain that is using the device. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-12-04driver core: Provide an wrapper around the mutex to do lockdep warningsKonrad Rzeszutek Wilk1-1/+1
Instead of open-coding it in drivers that want to double check that their functions are indeed holding the device lock. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Suggested-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-12-04xen/pciback: Don't deadlock when unbinding.Konrad Rzeszutek Wilk5-16/+33
As commit 0a9fd0152929db372ff61b0d6c280fdd34ae8bdb 'xen/pciback: Document the entry points for 'pcistub_put_pci_dev'' explained there are four entry points in this function. Two of them are when the user fiddles in the SysFS to unbind a device which might be in use by a guest or not. Both 'unbind' states will cause a deadlock as the the PCI lock has already been taken, which then pci_device_reset tries to take. We can simplify this by requiring that all callers of pcistub_put_pci_dev MUST hold the device lock. And then we can just call the lockless version of pci_device_reset. To make it even simpler we will modify xen_pcibk_release_pci_dev to quality whether it should take a lock or not - as it ends up calling xen_pcibk_release_pci_dev and needs to hold the lock. Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-10-12Merge tag 'stable/for-linus-3.18-rc0-tag' of ↵Linus Torvalds1-2/+4
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen updates from David Vrabel: "Features and fixes: - Add pvscsi frontend and backend drivers. - Remove _PAGE_IOMAP PTE flag, freeing it for alternate uses. - Try and keep memory contiguous during PV memory setup (reduces SWIOTLB usage). - Allow front/back drivers to use threaded irqs. - Support large initrds in PV guests. - Fix PVH guests in preparation for Xen 4.5" * tag 'stable/for-linus-3.18-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (22 commits) xen: remove DEFINE_XENBUS_DRIVER() macro xen/xenbus: Remove BUG_ON() when error string trucated xen/xenbus: Correct the comments for xenbus_grant_ring() x86/xen: Set EFER.NX and EFER.SCE in PVH guests xen: eliminate scalability issues from initrd handling xen: sync some headers with xen tree xen: make pvscsi frontend dependant on xenbus frontend arm{,64}/xen: Remove "EXPERIMENTAL" in the description of the Xen options xen-scsifront: don't deadlock if the ring becomes full x86: remove the Xen-specific _PAGE_IOMAP PTE flag x86/xen: do not use _PAGE_IOMAP PTE flag for I/O mappings x86: skip check for spurious faults for non-present faults xen/efi: Directly include needed headers xen-scsiback: clean up a type issue in scsiback_make_tpg() xen-scsifront: use GFP_ATOMIC under spin_lock MAINTAINERS: Add xen pvscsi maintainer xen-scsiback: Add Xen PV SCSI backend driver xen-scsifront: Add Xen PV SCSI frontend driver xen: Add Xen pvSCSI protocol description xen/events: support threaded irqs for interdomain event channels ...
2014-10-06xen: remove DEFINE_XENBUS_DRIVER() macroDavid Vrabel1-2/+4
The DEFINE_XENBUS_DRIVER() macro looks a bit weird and causes sparse errors. Replace the uses with standard structure definitions instead. This is similar to pci and usb device registration. Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-09-17xen/pciback: Use PCI device flag helper functionsEthan Zhao1-2/+2
Use PCI device flag helper functions when assigning or releasing device. No functional change. Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: David Vrabel <david.vrabel@citrix.com>
2014-08-12PCI: Remove DEFINE_PCI_DEVICE_TABLE macro useBenoit Taine1-1/+1
We should prefer `struct pci_device_id` over `DEFINE_PCI_DEVICE_TABLE` to meet kernel coding style guidelines. This issue was reported by checkpatch. A simplified version of the semantic patch that makes this change is as follows (http://coccinelle.lip6.fr/): // <smpl> @@ identifier i; declarer name DEFINE_PCI_DEVICE_TABLE; initializer z; @@ - DEFINE_PCI_DEVICE_TABLE(i) + const struct pci_device_id i[] = z; // </smpl> [bhelgaas: add semantic patch] Signed-off-by: Benoit Taine <benoit.taine@lip6.fr> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-08-01xen/pciback: Fix error return code in xen_pcibk_attach()Wei Yongjun1-0/+1
Fix to return -EFAULT from the error handling case instead of 0 when version mismatch with pcifront. Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Reviewed-by Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-06-03Merge branch 'locking-core-for-linus' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next Pull core locking updates from Ingo Molnar: "The main changes in this cycle were: - reduced/streamlined smp_mb__*() interface that allows more usecases and makes the existing ones less buggy, especially in rarer architectures - add rwsem implementation comments - bump up lockdep limits" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits) rwsem: Add comments to explain the meaning of the rwsem's count field lockdep: Increase static allocations arch: Mass conversion of smp_mb__*() arch,doc: Convert smp_mb__*() arch,xtensa: Convert smp_mb__*() arch,x86: Convert smp_mb__*() arch,tile: Convert smp_mb__*() arch,sparc: Convert smp_mb__*() arch,sh: Convert smp_mb__*() arch,score: Convert smp_mb__*() arch,s390: Convert smp_mb__*() arch,powerpc: Convert smp_mb__*() arch,parisc: Convert smp_mb__*() arch,openrisc: Convert smp_mb__*() arch,mn10300: Convert smp_mb__*() arch,mips: Convert smp_mb__*() arch,metag: Convert smp_mb__*() arch,m68k: Convert smp_mb__*() arch,m32r: Convert smp_mb__*() arch,ia64: Convert smp_mb__*() ...
2014-05-23xen/pciback: Document the entry points for 'pcistub_put_pci_dev'Konrad Rzeszutek Wilk1-0/+9
which are quite a few. It should be evident that dealing with that many options is a bit complex. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-05-23xen/pciback: Document when the 'unbind' and 'bind' functions are called.Konrad Rzeszutek Wilk1-0/+4
And also mention that you cannot do any pci_reset_function, pci_reset_slot, or such calls. This is because they take the same lock as SysFS does - and we would end up with a dead-lock if we call those functions. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-05-23xen-pciback: Document when we FLR an PCI device.Konrad Rzeszutek Wilk2-0/+6
When the toolstack wants us to drop or add an PCI device it changes the XenBus state to Configuring - and as result of that we find out which devices we should still be exporting out and which ones not. For the ones we don't need anymore we need to do an PCI reset so that it is ready for the next guest. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-05-23xen-pciback: First reset, then free.Konrad Rzeszutek Wilk1-1/+1
We were doing the operations of freeing and reset in the wrong order. Granted nothing broke because the reset functions just set bar->which = 0. But nonethless this was incorrect. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-05-23xen-pciback: Cleanup up pcistub_put_pci_devKonrad Rzeszutek Wilk1-5/+5
We are using 'psdev->dev','found_psdev->dev', and 'dev' at the same time - and they all point to the same structure. To keep it straight lets just use one - 'dev'. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-04-18arch: Mass conversion of smp_mb__*()Peter Zijlstra1-2/+2
Mostly scripted conversion of the smp_mb__* barriers. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-arch@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>