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Linux kernel
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kfree() is incorrectly used to release the pages allocated by
__get_free_page() and __get_free_pages(). Use the matching deallocators
i.e., free_page() and free_pages(), respectively.
Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
This reverts commit b3cf8528bb21febb650a7ecbf080d0647be40b9f.
That commit unintentionally broke Xen balloon memory hotplug with
"hotplug_unpopulated" set to 1. As long as "System RAM" resource
got assigned under a new "Unusable memory" resource in IO/Mem tree
any attempt to online this memory would fail due to general kernel
restrictions on having "System RAM" resources as 1st level only.
The original issue that commit has tried to workaround fa564ad96366
("x86/PCI: Enable a 64bit BAR on AMD Family 15h (Models 00-1f, 30-3f,
60-7f)") also got amended by the following 03a551734 ("x86/PCI: Move
and shrink AMD 64-bit window to avoid conflict") which made the
original fix to Xen ballooning unnecessary.
Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Add a missing header otherwise compiler warns about missed prototype:
drivers/xen/xlate_mmu.c:183:5: warning: no previous prototype for 'xen_xlate_unmap_gfn_range?' [-Wmissing-prototypes]
int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma,
^~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Srikanth Boddepalli <boddepalli.srikanth@gmail.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Joey Pabalinas <joeypabalinas@gmail.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Failure of an element of a Xen multicall is signalled via a WARN()
only if the kernel is compiled with MC_DEBUG. It is impossible to
know which element failed and why it did so.
Change that by printing the related information even without MC_DEBUG,
even if maybe in some limited form (e.g. without information which
caller produced the failing element).
Move the printing out of the switch statement in order to have the
same information for a single call.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
arch/x86/xen/spinlock.c includes several headers which are not needed.
Remove the #includes.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Currently the size of hypercall buffers allocated via
/dev/xen/hypercall is limited to a default of 64 memory pages. For live
migration of guests this might be too small as the page dirty bitmask
needs to be sized according to the size of the guest. This means
migrating a 8GB sized guest is already exhausting the default buffer
size for the dirty bitmap.
There is no sensible way to set a sane limit, so just remove it
completely. The device node's usage is limited to root anyway, so there
is no additional DOS scenario added by allowing unlimited buffers.
While at it make the error path for the -ENOMEM case a little bit
cleaner by setting n_pages to the number of successfully allocated
pages instead of the target size.
Fixes: c51b3c639e01f2 ("xen: add new hypercall buffer mapping device")
Cc: <stable@vger.kernel.org> #4.18
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Commit a856531951dc80 ("xen: make xen_qlock_wait() nestable")
introduced a regression for Xen guests running fully virtualized
(HVM or PVH mode). The Xen hypervisor wouldn't return from the poll
hypercall with interrupts disabled in case of an interrupt (for PV
guests it does).
So instead of disabling interrupts in xen_qlock_wait() use a nesting
counter to avoid calling xen_clear_irq_pending() in case
xen_qlock_wait() is nested.
Fixes: a856531951dc80 ("xen: make xen_qlock_wait() nestable")
Cc: stable@vger.kernel.org
Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Tested-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Juergen Gross <jgross@suse.com>
Commit 9da3f2b7405440 ("x86/fault: BUG() when uaccess helpers fault on
kernel addresses") introduced a regression for booting Xen PV guests.
Xen PV guests are using __put_user() and __get_user() for accessing the
p2m map (physical to machine frame number map) as accesses might fail
in case of not populated areas of the map.
With above commit using __put_user() and __get_user() for accessing
kernel pages is no longer valid. So replace the Xen hack by adding
appropriate p2m access functions using the default fixup handler.
Fixes: 9da3f2b7405440 ("x86/fault: BUG() when uaccess helpers fault on kernel addresses")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
info->nr_rings isn't adjusted in case of ENOMEM error from
negotiate_mq(). This leads to kernel panic in error path.
Typical call stack involving panic -
#8 page_fault at ffffffff8175936f
[exception RIP: blkif_free_ring+33]
RIP: ffffffffa0149491 RSP: ffff8804f7673c08 RFLAGS: 00010292
...
#9 blkif_free at ffffffffa0149aaa [xen_blkfront]
#10 talk_to_blkback at ffffffffa014c8cd [xen_blkfront]
#11 blkback_changed at ffffffffa014ea8b [xen_blkfront]
#12 xenbus_otherend_changed at ffffffff81424670
#13 backend_changed at ffffffff81426dc3
#14 xenwatch_thread at ffffffff81422f29
#15 kthread at ffffffff810abe6a
#16 ret_from_fork at ffffffff81754078
Cc: stable@vger.kernel.org
Fixes: 7ed8ce1c5fc7 ("xen-blkfront: move negotiate_mq to cover all cases of new VBDs")
Signed-off-by: Manjunath Patil <manjunath.b.patil@oracle.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
If a call to xenmem_reservation_increase() in gnttab_dma_free_pages()
fails it triggers a message "Failed to decrease reservation..." which
should be "Failed to increase reservation..."
Fixes: 9bdc7304f536 ('xen/grant-table: Allow allocating buffers suitable for DMA')
Reported-by: Ross Philipson <ross.philipson@oracle.com>
Signed-off-by: Liam Merwick <liam.merwick@oracle.com>
Reviewed-by: Mark Kanda <mark.kanda@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
xen_create_contiguous_region has now only an implementation if
CONFIG_XEN_PV is defined. However, on ARM we never set CONFIG_XEN_PV but
we do have an implementation of xen_create_contiguous_region which is
required for swiotlb-xen to work correctly (although it just sets
*dma_handle).
Cc: <stable@vger.kernel.org> # 4.12
Fixes: 16624390816c ("xen: create xen_create/destroy_contiguous_region() stubs for PVHVM only builds")
Signed-off-by: Stefano Stabellini <stefanos@xilinx.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
CC: Jeff.Kubascik@dornerworks.com
CC: Jarvis.Roach@dornerworks.com
CC: Nathan.Studer@dornerworks.com
CC: vkuznets@redhat.com
CC: boris.ostrovsky@oracle.com
CC: jgross@suse.com
CC: julien.grall@arm.com
Signed-off-by: Juergen Gross <jgross@suse.com>
xenbus_va_dev_error() will try to write error messages to Xenstore
under the error/<dev-name>/error node (with <dev-name> something like
"device/vbd/51872"). This will fail normally and another message
about this failure is added to dmesg.
I believe this is a remnant from very ancient times, as it was added
in the first pvops rush of commits in 2007.
So remove the additional message when writing to Xenstore failed as
a minimum step.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracel.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
A Xen PVH guest has no associated qemu device model, so trying to
unplug any emulated devices is making no sense at all.
Bail out early from xen_unplug_emulated_devices() when running as PVH
guest. This will avoid issuing the boot message:
[ 0.000000] Xen Platform PCI: unrecognised magic value
Cc: <stable@vger.kernel.org> # 4.11
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
It would be good for me to keep an eye on the patches that touch Xen
support in Linux to try to spot changes that break Xen on ARM early on.
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
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