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* Merge tag 'stable/for-linus-3.12-rc0-tag-three' of ↵Linus Torvalds2013-09-121-6/+7
|\ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen balloon driver bug-fixes from Stefano Stabellini: - fix a preemption bug in xen/balloon.c; - remove an harmful BUG_ON in xen/balloon.c that can trigger in non-erroneous situations. * tag 'stable/for-linus-3.12-rc0-tag-three' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/balloon: remove BUG_ON in increase_reservation xen/balloon: ensure preemption is disabled when using a scratch page
| * xen/balloon: remove BUG_ON in increase_reservationWei Liu2013-09-111-2/+0
| | | | | | | | | | | | | | | | | | The BUG_ON in increase_reservation is wrong as we have P2M entry ballooned out page set to balloon scratch page, so it might have a valid P2M entry at that point. Signed-off-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
| * xen/balloon: ensure preemption is disabled when using a scratch pageDavid Vrabel2013-09-111-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | In decrease_reservation(), if the kernel is preempted between updating the mapping and updating the p2m then they may end up using different scratch pages. Use get_balloon_scratch_page() and put_balloon_scratch_page() which use get_cpu_var() and put_cpu_var() to correctly disable preemption. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Tested-by: Sander Eikelenboom <linux@eikelenboom.it>
| * Merge tag 'v3.11-rc7' into stable/for-linus-3.12Konrad Rzeszutek Wilk2013-09-091-1/+12
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Linux 3.11-rc7 As we need the git commit 28817e9de4f039a1a8c1fe1df2fa2df524626b9e Author: Chuck Anderson <chuck.anderson@oracle.com> Date: Tue Aug 6 15:12:19 2013 -0700 xen/smp: initialize IPI vectors before marking CPU online * tag 'v3.11-rc7': (443 commits) Linux 3.11-rc7 ARC: [lib] strchr breakage in Big-endian configuration VFS: collect_mounts() should return an ERR_PTR bfs: iget_locked() doesn't return an ERR_PTR efs: iget_locked() doesn't return an ERR_PTR() proc: kill the extra proc_readfd_common()->dir_emit_dots() cope with potentially long ->d_dname() output for shmem/hugetlb usb: phy: fix build breakage USB: OHCI: add missing PCI PM callbacks to ohci-pci.c staging: comedi: bug-fix NULL pointer dereference on failed attach lib/lz4: correct the LZ4 license memcg: get rid of swapaccount leftovers nilfs2: fix issue with counting number of bio requests for BIO_EOPNOTSUPP error detection nilfs2: remove double bio_put() in nilfs_end_bio_write() for BIO_EOPNOTSUPP error drivers/platform/olpc/olpc-ec.c: initialise earlier ipv4: expose IPV4_DEVCONF ipv6: handle Redirect ICMP Message with no Redirected Header option be2net: fix disabling TX in be_close() Revert "ACPI / video: Always call acpi_video_init_brightness() on init" Revert "genetlink: fix family dump race" ... Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | | Merge tag 'stable/for-linus-3.12-rc0-tag' of ↵Linus Torvalds2013-09-048-142/+322
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen updates from Konrad Rzeszutek Wilk: "A couple of features and a ton of bug-fixes. There is also some maintership changes. Jeremy is enjoying the full-time work at the startup and as much as he would love to help - he can't find the time. I have a bunch of other things that I promised to work on - paravirt diet, get SWIOTLB working everywhere, etc, but haven't been able to find the time. As such both David Vrabel and Boris Ostrovsky have graciously volunteered to help with the maintership role. They will keep the lid on regressions, bug-fixes, etc. I will be in the background to help - but eventually there will be less of me doing the Xen GIT pulls and more of them. Stefano is still doing the ARM/ARM64 and will continue on doing so. Features: - Xen Trusted Platform Module (TPM) frontend driver - with the backend in MiniOS. - Scalability improvements in event channel. - Two extra Xen co-maintainers (David, Boris) and one going away (Jeremy) Bug-fixes: - Make the 1:1 mapping work during early bootup on selective regions. - Add scratch page to balloon driver to deal with unexpected code still holding on stale pages. - Allow NMIs on PV guests (64-bit only) - Remove unnecessary TLB flush in M2P code. - Fixes duplicate callbacks in Xen granttable code. - Fixes in PRIVCMD_MMAPBATCH ioctls to allow retries - Fix for events being lost due to rescheduling on different VCPUs. - More documentation" * tag 'stable/for-linus-3.12-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (23 commits) hvc_xen: Remove unnecessary __GFP_ZERO from kzalloc drivers/xen-tpmfront: Fix compile issue with missing option. xen/balloon: don't set P2M entry for auto translated guest xen/evtchn: double free on error Xen: Fix retry calls into PRIVCMD_MMAPBATCH*. xen/pvhvm: Initialize xen panic handler for PVHVM guests xen/m2p: use GNTTABOP_unmap_and_replace to reinstate the original mapping xen: fix ARM build after 6efa20e4 MAINTAINERS: Remove Jeremy from the Xen subsystem. xen/events: document behaviour when scanning the start word for events x86/xen: during early setup, only 1:1 map the ISA region x86/xen: disable premption when enabling local irqs swiotlb-xen: replace dma_length with sg_dma_len() macro swiotlb: replace dma_length with sg_dma_len() macro xen/balloon: set a mapping for ballooned out pages xen/evtchn: improve scalability by using per-user locks xen/p2m: avoid unneccesary TLB flush in m2p_remove_override() MAINTAINERS: Add in two extra co-maintainers of the Xen tree. MAINTAINERS: Update the Xen subsystem's with proper mailing list. xen: replace strict_strtoul() with kstrtoul() ...
| * | xen/balloon: don't set P2M entry for auto translated guestWei Liu2013-08-301-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In commit cd9151e2: xen/balloon: set a mapping for ballooned out pages we have the ballooned out page's mapping set to a scratch page. That commit also sets the P2M entry of ballooned out page to the scratch page's MFN. This is necessary for PV guest but not for HVM guest. On the other hand, setting the P2M entry would trigger BUG_ON in __set_phys_to_machine. The correct thing to do here is to avoid calling __set_phys_to_machine for auto translated guest. Signed-off-by: Wei Liu <wei.liu2@citrix.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
| * | xen/evtchn: double free on errorDan Carpenter2013-08-301-1/+0
| | | | | | | | | | | | | | | | | | | | | The call to del_evtchn() frees "evtchn". Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | Xen: Fix retry calls into PRIVCMD_MMAPBATCH*.Andres Lagar-Cavilla2013-08-301-20/+63
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a foreign mapper attempts to map guest frames that are paged out, the mapper receives an ENOENT response and will have to try again while a helper process pages the target frame back in. Gating checks on PRIVCMD_MMAPBATCH* ioctl args were preventing retries of mapping calls. Permit subsequent calls to update a sub-range of the VMA, iff nothing is yet mapped in that range. Since it is now valid to call PRIVCMD_MMAPBATCH* multiple times, only set vma->vm_private_data if the parameters are valid and (if necessary) the pages for the auto_translated_physmap case have been allocated. This prevents subsequent calls from incorrectly entering the 'retry' path when there are no pages allocated etc. Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen/m2p: use GNTTABOP_unmap_and_replace to reinstate the original mappingStefano Stabellini2013-08-201-9/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GNTTABOP_unmap_grant_ref unmaps a grant and replaces it with a 0 mapping instead of reinstating the original mapping. Doing so separately would be racy. To unmap a grant and reinstate the original mapping atomically we use GNTTABOP_unmap_and_replace. GNTTABOP_unmap_and_replace doesn't work with GNTMAP_contains_pte, so don't use it for kmaps. GNTTABOP_unmap_and_replace zeroes the mapping passed in new_addr so we have to reinstate it, however that is a per-cpu mapping only used for balloon scratch pages, so we can be sure that it's not going to be accessed while the mapping is not valid. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> CC: alex@alex.org.uk CC: dcrisan@flexiant.com [v1: Konrad fixed up the conflicts] Conflicts: arch/x86/xen/p2m.c
| * | xen: fix ARM build after 6efa20e4Stefano Stabellini2013-08-201-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following commit: commit 6efa20e49b9cb1db1ab66870cc37323474a75a13 Author: Konrad Rzeszutek Wilk <konrad@kernel.org> Date: Fri Jul 19 11:51:31 2013 -0400 xen: Support 64-bit PV guest receiving NMIs breaks the Xen ARM build: CC drivers/xen/events.o drivers/xen/events.c: In function 'xen_send_IPI_one': drivers/xen/events.c:1218:6: error: 'XEN_NMI_VECTOR' undeclared (first use in this function) Simply ifdef the undeclared symbol in the code. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
| * | xen/events: document behaviour when scanning the start word for eventsDavid Vrabel2013-08-201-5/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The original comment on the scanning of the start word on the 2nd pass did not reflect the actual behaviour (the code was incorrectly masking bit_idx instead of the pending word itself). The documented behaviour is not actually required since if event were pending in the MSBs, they would be immediately scanned anyway as we go through the loop again. Update the documentation to reflect this (instead of trying to change the behaviour). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
| * | swiotlb-xen: replace dma_length with sg_dma_len() macroStefano Stabellini2013-08-091-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | swiotlb-xen has an implicit dependency on CONFIG_NEED_SG_DMA_LENGTH. Remove it by replacing dma_length with sg_dma_len. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen/balloon: set a mapping for ballooned out pagesStefano Stabellini2013-08-091-3/+66
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently ballooned out pages are mapped to 0 and have INVALID_P2M_ENTRY in the p2m. These ballooned out pages are used to map foreign grants by gntdev and blkback (see alloc_xenballooned_pages). Allocate a page per cpu and map all the ballooned out pages to the corresponding mfn. Set the p2m accordingly. This way reading from a ballooned out page won't cause a kernel crash (see http://lists.xen.org/archives/html/xen-devel/2012-12/msg01154.html). Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> CC: alex@alex.org.uk CC: dcrisan@flexiant.com Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen/evtchn: improve scalability by using per-user locksDavid Vrabel2013-08-091-80/+112
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The global array of port users and the port_user_lock limits scalability of the evtchn device. Instead of the global array lookup, use a per-use (per-fd) tree of event channels bound by that user and protect the tree with a per-user lock. This is also a prerequiste for extended the number of supported event channels, by removing the fixed size, per-event channel array. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen: replace strict_strtoul() with kstrtoul()Jingoo Han2013-08-091-18/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | The usage of strict_strtoul() is not preferred, because strict_strtoul() is obsolete. Thus, kstrtoul() should be used. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen-gnt: prevent adding duplicate gnt callbacksRoger Pau Monne2013-08-091-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the current implementation, the callback in the tail of the list can be added twice, because the check done in gnttab_request_free_callback is bogus, callback->next can be NULL if it is the last callback in the list. If we add the same callback twice we end up with an infinite loop, were callback == callback->next. Replace this check with a proper one that iterates over the list to see if the callback has already been added. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Matt Wilson <msw@amazon.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> CC: stable@vger.kernel.org
| * | xen: Support 64-bit PV guest receiving NMIsKonrad Rzeszutek Wilk2013-08-091-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is based on a patch that Zhenzhong Duan had sent - which was missing some of the remaining pieces. The kernel has the logic to handle Xen-type-exceptions using the paravirt interface in the assembler code (see PARAVIRT_ADJUST_EXCEPTION_FRAME - pv_irq_ops.adjust_exception_frame and and INTERRUPT_RETURN - pv_cpu_ops.iret). That means the nmi handler (and other exception handlers) use the hypervisor iret. The other changes that would be neccessary for this would be to translate the NMI_VECTOR to one of the entries on the ipi_vector and make xen_send_IPI_mask_allbutself use different events. Fortunately for us commit 1db01b4903639fcfaec213701a494fe3fb2c490b (xen: Clean up apic ipi interface) implemented this and we piggyback on the cleanup such that the apic IPI interface will pass the right vector value for NMI. With this patch we can trigger NMIs within a PV guest (only tested x86_64). For this to work with normal PV guests (not initial domain) we need the domain to be able to use the APIC ops - they are already implemented to use the Xen event channels. For that to be turned on in a PV domU we need to remove the masking of X86_FEATURE_APIC. Incidentally that means kgdb will also now work within a PV guest without using the 'nokgdbroundup' workaround. Note that the 32-bit version is different and this patch does not enable that. CC: Lisa Nguyen <lisa@xenapiadmin.com> CC: Ben Guthro <benjamin.guthro@citrix.com> CC: Zhenzhong Duan <zhenzhong.duan@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [v1: Fixed up per David Vrabel comments] Reviewed-by: Ben Guthro <benjamin.guthro@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
* | | Merge branch 'acpi-sleep'Rafael J. Wysocki2013-08-271-13/+28
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | * acpi-sleep: x86 / tboot / ACPI: Fail extended mode reduced hardware sleep xen / ACPI: notify xen when reduced hardware sleep is available ACPI / sleep: Introduce acpi_os_prepare_extended_sleep() for extended sleep path
| * | xen / ACPI: notify xen when reduced hardware sleep is availableBen Guthro2013-07-311-13/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use the acpi_os_prepare_extended_sleep() callback to notify xen to make use of the reduced hardware sleep functionality The xen hypervisor change underlying this is commit 62d1a69 ("ACPI: support v5 (reduced HW) sleep interface") on the master branch of git://xenbits.xen.org/xen.git. Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Ben Guthro <benjamin.guthro@citrix.com> Acked-by: Konrad Wilk <konrad.wilk@oracle.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | | Merge tag 'stable/for-linus-3.11-rc6-tag' of ↵Linus Torvalds2013-08-211-1/+12
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen bug-fixes from Konrad Rzeszutek Wilk: - On ARM did not have balanced calls to get/put_cpu. - Fix to make tboot + Xen + Linux correctly. - Fix events VCPU binding issues. - Fix a vCPU online race where IPIs are sent to not-yet-online vCPU. * tag 'stable/for-linus-3.11-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/smp: initialize IPI vectors before marking CPU online xen/events: mask events when changing their VCPU binding xen/events: initialize local per-cpu mask for all possible events x86/xen: do not identity map UNUSABLE regions in the machine E820 xen/arm: missing put_cpu in xen_percpu_init
| * | xen/events: mask events when changing their VCPU bindingDavid Vrabel2013-08-201-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a event is being bound to a VCPU there is a window between the EVTCHNOP_bind_vpcu call and the adjustment of the local per-cpu masks where an event may be lost. The hypervisor upcalls the new VCPU but the kernel thinks that event is still bound to the old VCPU and ignores it. There is even a problem when the event is being bound to the same VCPU as there is a small window beween the clear_bit() and set_bit() calls in bind_evtchn_to_cpu(). When scanning for pending events, the kernel may read the bit when it is momentarily clear and ignore the event. Avoid this by masking the event during the whole bind operation. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> CC: stable@vger.kernel.org
| * | xen/events: initialize local per-cpu mask for all possible eventsDavid Vrabel2013-08-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The sizeof() argument in init_evtchn_cpu_bindings() is incorrect resulting in only the first 64 (or 32 in 32-bit guests) ports having their bindings being initialized to VCPU 0. In most cases this does not cause a problem as request_irq() will set the irq affinity which will set the correct local per-cpu mask. However, if the request_irq() is called on a VCPU other than 0, there is a window between the unmasking of the event and the affinity being set were an event may be lost because it is not locally unmasked on any VCPU. If request_irq() is called on VCPU 0 then local irqs are disabled during the window and the race does not occur. Fix this by initializing all NR_EVENT_CHANNEL bits in the local per-cpu masks. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> CC: stable@vger.kernel.org
* | | Merge tag 'stable/for-linus-3.11-rc3-tag' of ↵Linus Torvalds2013-07-314-26/+21
|\| | | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen fixes from Konrad Rzeszutek Wilk: - Three fixes for ARM/ARM64 to either compile or not certain generic drivers - Fix for avoiding a potential deadlock when an user space event channel is destroyed. - Fix a workqueue resuming multiple times. * tag 'stable/for-linus-3.11-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/tmem: do not allow XEN_TMEM on ARM64 xen/evtchn: avoid a deadlock when unbinding an event channel xen/arm: enable PV control for ARM xen/arm64: Don't compile cpu hotplug xenbus: frontend resume cleanup
| * xen/tmem: do not allow XEN_TMEM on ARM64Stefano Stabellini2013-07-301-1/+1
| | | | | | | | | | | | | | | | tmem is not supported on arm or arm64 yet. Will revert this once the Xen hypervisor supports it. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * xen/evtchn: avoid a deadlock when unbinding an event channelDavid Vrabel2013-07-301-19/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unbinding an event channel (either with the ioctl or when the evtchn device is closed) may deadlock because disable_irq() is called with port_user_lock held which is also locked by the interrupt handler. Think of the IOCTL_EVTCHN_UNBIND is being serviced, the routine has just taken the lock, and an interrupt happens. The evtchn_interrupt is invoked, tries to take the lock and spins forever. A quick glance at the code shows that the spinlock is a local IRQ variant. Unfortunately that does not help as "disable_irq() waits for the interrupt handler on all CPUs to stop running. If the irq occurs on another VCPU, it tries to take port_user_lock and can't because the unbind ioctl is holding it." (from David). Hence we cannot depend on the said spinlock to protect us. We could make it a system wide IRQ disable spinlock but there is a better way. We can piggyback on the fact that the existence of the spinlock is to make get_port_user() checks be up-to-date. And we can alter those checks to not depend on the spin lock (as it's protected by u->bind_mutex in the ioctl) and can remove the unnecessary locking (this is IOCTL_EVTCHN_UNBIND) path. In the interrupt handler we cannot use the mutex, but we do not need it. "The unbind disables the irq before making the port user stale, so when you clear it you are guaranteed that the interrupt handler that might use that port cannot be running." (from David). Hence this patch removes the spinlock usage on the teardown path and piggybacks on disable_irq happening before we muck with the get_port_user() data. This ensures that the interrupt handler will never run on stale data. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [v1: Expanded the commit description a bit]
| * xen/arm: enable PV control for ARMJulien Grall2013-07-291-2/+1
| | | | | | | | | | | | | | | | | | Enable lifecyle management (reboot, shutdown...) from the toolstack for ARM guests. Signed-off-by: Julien Grall <julien.grall@linaro.org> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
| * xen/arm64: Don't compile cpu hotplugJulien Grall2013-07-291-1/+1
| | | | | | | | | | | | | | | | | | On ARM64, when CONFIG_XEN=y, the compilation will fail because CPU hotplug is not yet supported with XEN. For now, disable it. Signed-off-by: Julien Grall <julien.grall@linaro.org> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Mark Rutland <mark.rutland@arm.com>
| * xenbus: frontend resume cleanupAurelien Chartier2013-07-291-3/+16
| | | | | | | | | | | | | | | | | | | | | | Only create the delayed resume workqueue if we are running in the same domain as xenstored and issue a warning if the workqueue creation fails. Move the work initialization to the device probe so it is done only once. Signed-off-by: Aurelien Chartier <aurelien.chartier@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
* | drivers: delete __cpuinit usage from all remaining drivers filesPaul Gortmaker2013-07-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. This removes all the remaining one-off uses of the __cpuinit macros from all C files in the drivers/* directory. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* | Merge branch 'timers-core-for-linus' of ↵Linus Torvalds2013-07-061-3/+0
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer core updates from Thomas Gleixner: "The timer changes contain: - posix timer code consolidation and fixes for odd corner cases - sched_clock implementation moved from ARM to core code to avoid duplication by other architectures - alarm timer updates - clocksource and clockevents unregistration facilities - clocksource/events support for new hardware - precise nanoseconds RTC readout (Xen feature) - generic support for Xen suspend/resume oddities - the usual lot of fixes and cleanups all over the place The parts which touch other areas (ARM/XEN) have been coordinated with the relevant maintainers. Though this results in an handful of trivial to solve merge conflicts, which we preferred over nasty cross tree merge dependencies. The patches which have been committed in the last few days are bug fixes plus the posix timer lot. The latter was in akpms queue and next for quite some time; they just got forgotten and Frederic collected them last minute." * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (59 commits) hrtimer: Remove unused variable hrtimers: Move SMP function call to thread context clocksource: Reselect clocksource when watchdog validated high-res capability posix-cpu-timers: don't account cpu timer after stopped thread runtime accounting posix_timers: fix racy timer delta caching on task exit posix-timers: correctly get dying task time sample in posix_cpu_timer_schedule() selftests: add basic posix timers selftests posix_cpu_timers: consolidate expired timers check posix_cpu_timers: consolidate timer list cleanups posix_cpu_timer: consolidate expiry time type tick: Sanitize broadcast control logic tick: Prevent uncontrolled switch to oneshot mode tick: Make oneshot broadcast robust vs. CPU offlining x86: xen: Sync the CMOS RTC as well as the Xen wallclock x86: xen: Sync the wallclock when the system time is set timekeeping: Indicate that clock was set in the pvclock gtod notifier timekeeping: Pass flags instead of multiple bools to timekeeping_update() xen: Remove clock_was_set() call in the resume path hrtimers: Support resuming with two or more CPUs online (but stopped) timer: Fix jiffies wrap behavior of round_jiffies_common() ...
| * \ Merge branch 'timers/posix-cpu-timers-for-tglx' ofThomas Gleixner2013-07-0412-128/+126
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into timers/core Frederic sayed: "Most of these patches have been hanging around for several month now, in -mmotm for a significant chunk. They already missed a few releases." Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | xen: Remove clock_was_set() call in the resume pathDavid Vrabel2013-06-281-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 359cdd3f866(xen: maintain clock offset over save/restore) added a clock_was_set() call into the xen resume code to propagate the system time changes. With the modified hrtimer resume code, which makes sure that all cpus are notified this call is not longer necessary. [ tglx: Separated it from the hrtimer change ] Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: John Stultz <john.stultz@linaro.org> Cc: <xen-devel@lists.xen.org> Link: http://lkml.kernel.org/r/1372329348-20841-2-git-send-email-david.vrabel@citrix.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | | | Merge branch 'akpm' (updates from Andrew Morton)Linus Torvalds2013-07-032-19/+6
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge first patch-bomb from Andrew Morton: - various misc bits - I'm been patchmonkeying ocfs2 for a while, as Joel and Mark have been distracted. There has been quite a bit of activity. - About half the MM queue - Some backlight bits - Various lib/ updates - checkpatch updates - zillions more little rtc patches - ptrace - signals - exec - procfs - rapidio - nbd - aoe - pps - memstick - tools/testing/selftests updates * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (445 commits) tools/testing/selftests: don't assume the x bit is set on scripts selftests: add .gitignore for kcmp selftests: fix clean target in kcmp Makefile selftests: add .gitignore for vm selftests: add hugetlbfstest self-test: fix make clean selftests: exit 1 on failure kernel/resource.c: remove the unneeded assignment in function __find_resource aio: fix wrong comment in aio_complete() drivers/w1/slaves/w1_ds2408.c: add magic sequence to disable P0 test mode drivers/memstick/host/r592.c: convert to module_pci_driver drivers/memstick/host/jmb38x_ms: convert to module_pci_driver pps-gpio: add device-tree binding and support drivers/pps/clients/pps-gpio.c: convert to module_platform_driver drivers/pps/clients/pps-gpio.c: convert to devm_* helpers drivers/parport/share.c: use kzalloc Documentation/accounting/getdelays.c: avoid strncpy in accounting tool aoe: update internal version number to v83 aoe: update copyright date aoe: perform I/O completions in parallel ...
| * | | | drivers: avoid format string in dev_set_nameKees Cook2013-07-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Calling dev_set_name with a single paramter causes it to be handled as a format string. Many callers are passing potentially dynamic string content, so use "%s" in those cases to avoid any potential accidents, including wrappers like device_create*() and bdi_register(). Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | mm: correctly update zone->managed_pagesJiang Liu2013-07-031-18/+5
| | |/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Enhance adjust_managed_page_count() to adjust totalhigh_pages for highmem pages. And change code which directly adjusts totalram_pages to use adjust_managed_page_count() because it adjusts totalram_pages, totalhigh_pages and zone->managed_pages altogether in a safe way. Remove inc_totalhigh_pages() and dec_totalhigh_pages() from xen/balloon driver bacause adjust_managed_page_count() has already adjusted totalhigh_pages. This patch also fixes two bugs: 1) enhances virtio_balloon driver to adjust totalhigh_pages when reserve/unreserve pages. 2) enhance memory_hotplug.c to adjust totalhigh_pages when hot-removing memory. We still need to deal with modifications of totalram_pages in file arch/powerpc/platforms/pseries/cmm.c, but need help from PPC experts. [akpm@linux-foundation.org: remove ifdef, per Wanpeng Li, virtio_balloon.c cleanup, per Sergei] [akpm@linux-foundation.org: export adjust_managed_page_count() to modules, for drivers/virtio/virtio_balloon.c] Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <sworddragon2@aol.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | Merge tag 'stable/for-linus-3.11-rc0-tag-two' of ↵Linus Torvalds2013-07-0333-198/+221
|\ \ \ \ | |/ / / |/| | / | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen bugfixes from Konrad Rzeszutek Wilk: - Fix memory leak when CPU hotplugging. - Compile bugs with various #ifdefs - Fix state changes in Xen PCI front not dealing well with new toolstack. - Cleanups in code (use pr_*, fix 80 characters splits, etc) - Long standing bug in double-reporting the steal time * tag 'stable/for-linus-3.11-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/time: remove blocked time accounting from xen "clockchip" xen: Convert printks to pr_<level> xen: ifdef CONFIG_HIBERNATE_CALLBACKS xen_*_suspend xen/pcifront: Deal with toolstack missing 'XenbusStateClosing' state. xen/time: Free onlined per-cpu data structure if we want to online it again. xen/time: Check that the per_cpu data structure has data before freeing. xen/time: Don't leak interrupt name when offlining. xen/time: Encapsulate the struct clock_event_device in another structure. xen/spinlock: Don't leak interrupt name when offlining. xen/smp: Don't leak interrupt name when offlining. xen/smp: Set the per-cpu IRQ number to a valid default. xen/smp: Introduce a common structure to contain the IRQ name and interrupt line. xen/smp: Coalesce the free_irq calls in one function. xen-pciback: fix error return code in pcistub_irq_handler_switch()
| * | xen: Convert printks to pr_<level>Joe Perches2013-06-2833-194/+213
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Convert printks to pr_<level> (excludes printk(KERN_DEBUG...) to be more consistent throughout the xen subsystem. Add pr_fmt with KBUILD_MODNAME or "xen:" KBUILD_MODNAME Coalesce formats and add missing word spaces Add missing newlines Align arguments and reflow to 80 columns Remove DRV_NAME from formats as pr_fmt adds the same content This does change some of the prefixes of these messages but it also does make them more consistent. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen: ifdef CONFIG_HIBERNATE_CALLBACKS xen_*_suspendStefano Stabellini2013-06-281-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xen_hvm_post_suspend, xen_pre_suspend, xen_post_suspend are only used if CONFIG_HIBERNATE_CALLBACKS is defined, resulting in: drivers/xen/manage.c:46:13: warning: ‘xen_hvm_post_suspend’ defined but not used [-Wunused-function] drivers/xen/manage.c:52:13: warning: ‘xen_pre_suspend’ defined but not used [-Wunused-function] drivers/xen/manage.c:59:13: warning: ‘xen_post_suspend’ defined but not used [-Wunused-function] If the kernel config is missing CONFIG_HIBERNATE_CALLBACKS. Simply ifdef CONFIG_HIBERNATE_CALLBACKS the three functions. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen-pciback: fix error return code in pcistub_irq_handler_switch()Wei Yongjun2013-06-101-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix to return -ENOENT in the pcistub_device_find() and pci_get_drvdata() error handling case instead of 0(overwrite to 0 by str_to_slot()), as done elsewhere in this function. Acked-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | | xen/tmem: Don't over-write tmem_frontswap_poolid after tmem_frontswap_init ↵Konrad Rzeszutek Wilk2013-06-101-2/+2
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | set it. Commit 10a7a0771399a57a297fca9615450dbb3f88081a ("xen: tmem: enable Xen tmem shim to be built/loaded as a module") allows the tmem module to be loaded any time. For this work the frontswap API had to be able to asynchronously to call tmem_frontswap_init before or after the swap image had been set. That was added in git commit 905cd0e1bf9ffe82d6906a01fd974ea0f70be97a ("mm: frontswap: lazy initialization to allow tmem backends to build/run as modules"). Which means we could do this (The common case): modprobe tmem [so calls frontswap_register_ops, no ->init] modifies tmem_frontswap_poolid = -1 swapon /dev/xvda1 [__frontswap_init, calls -> init, tmem_frontswap_poolid is < 0 so tmem hypercall done] Or the failing one: swapon /dev/xvda1 [calls __frontswap_init, sets the need_init bitmap] modprobe tmem [calls frontswap_register_ops, -->init calls, finds out tmem_frontswap_poolid is 0, does not make a hypercall. Later in the module_init, sets tmem_frontswap_poolid=-1] Which meant that in the failing case we would not call the hypercall to initialize the pool and never be able to make any frontswap backend calls. Moving the frontswap_register_ops after setting the tmem_frontswap_poolid fixes it. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Bob Liu <bob.liu@oracle.com>
* | xenbus_client.c: correct exit path for xenbus_map_ring_valloc_hvmWei Liu2013-05-291-2/+3
| | | | | | | | | | | | | | | | | | Apparently we should not free page that has not been allocated. This is b/c alloc_xenballooned_pages will take care of freeing the page on its own. Signed-off-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | xen-pciback: more uses of cached MSI-X capability offsetJan Beulich2013-05-291-2/+2
| | | | | | | | | | Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | xenbus: save xenstore local status for later useAurelien Chartier2013-05-293-15/+20
| | | | | | | | | | | | | | | | | | | | | | Save the xenstore local status computed in xenbus_init. It can then be used later to check if xenstored is running in this domain. Signed-off-by: Aurelien Chartier <aurelien.chartier@citrix.com> [Changes in v4: - Change variable name to xen_store_domain_type] Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | xenbus: delay xenbus frontend resume if xenstored is not runningAurelien Chartier2013-05-291-1/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the xenbus frontend is located in a domain running xenstored, the device resume is hanging because it is happening before the process resume. This patch adds extra logic to the resume code to check if we are the domain running xenstored and delay the resume if needed. Signed-off-by: Aurelien Chartier <aurelien.chartier@citrix.com> [Changes in v2: - Instead of bypassing the resume, process it in a workqueue] [Changes in v3: - Add a struct work in xenbus_device to avoid dynamic allocation - Several small code fixes] [Changes in v4: - Use a dedicated workqueue] [Changes in v5: - Move create_workqueue error handling to xenbus_frontend_dev_resume] Acked-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | xmem/tmem: fix 'undefined variable' build error.Frederico Cadete2013-05-281-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | In the (not so useful) kernel configuration where CONFIG_SWAP is undefined and CONFIG_XEN_SELFBALLOONING is defined, xen_tmem_init would use undefined variable 'static bool frontswap'. Added #else to have #define frontswap (0) in the case where CONFIG_FRONTSWAP is not defined. Signed-off-by: Frederico Cadete <frederico@cadete.eu> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | xen: Fixed assignment error in if statementLisa Nguyen2013-05-201-1/+2
| | | | | | | | | | | | | | Fixed assignment error in if statement in balloon.c Signed-off-by: Lisa Nguyen <lisa@xenapiadmin.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | xen/xenbus: Fixed over 80 character limit issueLisa Nguyen2013-05-201-1/+2
| | | | | | | | | | | | | | | | | | Fixed the format length of the xenbus_backend_ioctl() function to meet the 80 character limit in xenbus_dev_backend.c Signed-off-by: Lisa Nguyen <lisa@xenapiadmin.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | xen/xenbus: Fixed indentation error in switch caseLisa Nguyen2013-05-201-10/+8
| | | | | | | | | | | | | | | | Fixed the indentation error in the switch case in xenbus_dev_backend.c Signed-off-by: Lisa Nguyen <lisa@xenapiadmin.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | xen/tmem: Don't use self[ballooning|shrinking] if frontswap is off.Konrad Rzeszutek Wilk2013-05-152-9/+14
| | | | | | | | | | | | | | | | | | | | There is no point. We would just squeeze the guest to put more and more pages in the swap disk without any purpose. The only time it makes sense to use the selfballooning and shrinking is when frontswap is being utilized. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | xen/tmem: Remove the usage of '[no|]selfballoon' and use ↵Konrad Rzeszutek Wilk2013-05-152-26/+4
| | | | | | | | | | | | | | | | | | | | 'tmem.selfballooning' bool instead. As the 'tmem' driver is the one that actually sets whether it will use it (or not) so might as well make tmem responsible for this knob. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>