Konrad Rzeszutek Wilk [Mon, 16 Nov 2015 17:40:48 +0000 (12:40 -0500)]
xen/pciback: Save xen_pci_op commands before processing it
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>
(cherry picked from commit 8135cf8b092723dbfcc611fe6fdcb3a36c9951c5) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Roger Pau Monné [Tue, 3 Nov 2015 16:40:43 +0000 (16:40 +0000)]
xen-blkback: read from indirect descriptors only once
Since indirect descriptors are in memory shared with the frontend, the
frontend could alter the first_sect and last_sect values after they have
been validated but before they are recorded in the request. This may
result in I/O requests that overflow the foreign page, possibly
overwriting local pages when the I/O request is executed.
When parsing indirect descriptors, only read first_sect and last_sect
once.
This is part of XSA155.
CC: stable@vger.kernel.org Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
(cherry picked from commit 18779149101c0dd43ded43669ae2a92d21b6f9cb) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
David Vrabel [Fri, 30 Oct 2015 15:17:06 +0000 (15:17 +0000)]
xen-netback: use RING_COPY_REQUEST() throughout
Instead of open-coding memcpy()s and directly accessing Tx and Rx
requests, use the new RING_COPY_REQUEST() that ensures the local copy
is correct.
This is more than is strictly necessary for guest Rx requests since
only the id and gref fields are used and it is harmless if the
frontend modifies these.
This is part of XSA155.
CC: stable@vger.kernel.org Reviewed-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
(cherry picked from commit 68a33bfd8403e4e22847165d149823a2e0e67c9c) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
David Vrabel [Fri, 30 Oct 2015 15:16:01 +0000 (15:16 +0000)]
xen-netback: don't use last request to determine minimum Tx credit
The last from guest transmitted request gives no indication about the
minimum amount of credit that the guest might need to send a packet
since the last packet might have been a small one.
Instead allow for the worst case 128 KiB packet.
This is part of XSA155.
CC: stable@vger.kernel.org Reviewed-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
(cherry picked from commit 0f589967a73f1f30ab4ac4dd9ce0bb399b4d6357) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
David Vrabel [Fri, 30 Oct 2015 14:58:08 +0000 (14:58 +0000)]
xen: Add RING_COPY_REQUEST()
Using RING_GET_REQUEST() on a shared ring is easy to use incorrectly
(i.e., by not considering that the other end may alter the data in the
shared ring while it is being inspected). Safe usage of a request
generally requires taking a local copy.
Provide a RING_COPY_REQUEST() macro to use instead of
RING_GET_REQUEST() and an open-coded memcpy(). This takes care of
ensuring that the copy is done correctly regardless of any possible
compiler optimizations.
Use a volatile source to prevent the compiler from reordering or
omitting the copy.
This is part of XSA155.
CC: stable@vger.kernel.org Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
(cherry picked from commit 454d5d882c7e412b840e3c99010fe81a9862f6fb) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Boris Ostrovsky [Sun, 13 Dec 2015 00:25:55 +0000 (19:25 -0500)]
xen/x86/pvh: Use HVM's flush_tlb_others op
Using MMUEXT_TLB_FLUSH_MULTI doesn't buy us much since the hypervisor
will likely perform same IPIs as would have the guest.
More importantly, using MMUEXT_INVLPG_MULTI may not to invalidate the
guest's address on remote CPU (when, for example, VCPU from another guest
is running there).
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Suggested-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 20f36e0380a7e871a711d5e4e59d04d4948326b4) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Boris Ostrovsky [Wed, 2 Dec 2015 17:10:48 +0000 (12:10 -0500)]
xen: Resume PMU from non-atomic context
Resuming PMU currently triggers a warning from ___might_sleep() (assuming
CONFIG_DEBUG_ATOMIC_SLEEP is set) when xen_pmu_init() allocates GFP_KERNEL
page because we are in state resembling atomic context.
Move resuming PMU to xen_arch_resume() which is called in regular context.
For symmetry move suspending PMU to xen_arch_suspend() as well.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: <stable@vger.kernel.org> # 4.3 Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit de0afc9bdeeadaa998797d2333c754bf9f4d5dcf) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Ross Lagerwall [Fri, 19 Jun 2015 15:15:57 +0000 (16:15 +0100)]
xen/events/fifo: Consume unprocessed events when a CPU dies
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> Cc: <stable@vger.kernel.org> # 3.14+ Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 3de88d622fd68bd4dbee0f80168218b23f798fd0) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
David Vrabel [Thu, 26 Nov 2015 16:14:35 +0000 (16:14 +0000)]
xen/evtchn: dynamically grow pending event channel ring
If more than 1024 event channels are bound to a evtchn device then it
possible (even with well behaved applications) for the ring to
overflow and events to be lost (reported as an -EFBIG error).
Dynamically increase the size of the ring so there is always enough
space for all bound events. Well behaved applicables that only unmask
events after draining them from the ring can thus no longer lose
events.
However, an application could unmask an event before draining it,
allowing multiple entries per port to accumulate in the ring, and a
overflow could still occur. So the overflow detection and reporting
is retained.
The ring size is initially only 64 entries so the common use case of
an application only binding a few events will use less memory than
before. The ring size may grow to 512 KiB (enough for all 2^17
possible channels). This order 7 kmalloc() may fail due to memory
fragmentation, so we fall back to trying vmalloc().
Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit 8620015499101090ae275bf11e9bc2f9febfdf08) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Boris Ostrovsky [Tue, 10 Nov 2015 20:10:33 +0000 (15:10 -0500)]
xen/gntdev: Grant maps should not be subject to NUMA balancing
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> Cc: stable@vger.kernel.org Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 9c17d96500f78d7ecdb71ca6942830158bc75a2b) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Zhenzhong Duan [Tue, 27 Oct 2015 19:19:52 +0000 (15:19 -0400)]
xen: fix the check of e_pfn in xen_find_pfn_range
On some NUMA system, after dom0 up, we see below warning even if there are
enough pfn ranges that could be used for remapping:
"Unable to find available pfn range, not remapping identity pages"
Fix it to avoid getting a memory region of zero size in xen_find_pfn_range.
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit abed7d0710e8f892c267932a9492ccf447674fb8) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Stefano Stabellini [Thu, 22 Oct 2015 16:21:46 +0000 (16:21 +0000)]
xen, cpu_hotplug: call device_offline instead of cpu_down
When offlining a cpu, instead of cpu_down, call device_offline, which
also takes care of updating the cpu.dev.offline field. This keeps the
sysfs file /sys/devices/system/cpu/cpuN/online, up to date. Also move
the call to disable_hotplug_cpu, because it makes more sense to have it
there.
We don't call device_online at cpu-hotplug time, because that would
immediately take the cpu online, while we want to retain the current
behaviour: the user needs to explicitly enable the cpu after it has
been hotplugged.
Stefano Stabellini [Thu, 22 Oct 2015 16:20:46 +0000 (16:20 +0000)]
xen/arm: Enable cpu_hotplug.c
Build cpu_hotplug for ARM and ARM64 guests.
Rename arch_(un)register_cpu to xen_(un)register_cpu and provide an
empty implementation on ARM and ARM64. On x86 just call
arch_(un)register_cpu as we are already doing.
Julien Grall [Tue, 13 Oct 2015 16:50:13 +0000 (17:50 +0100)]
xenbus: Support multiple grants ring with 64KB
The PV ring may use multiple grants and expect them to be mapped
contiguously in the virtual memory.
Although, the current code is relying on a Linux page will be mapped to
a single grant. On build where Linux is using a different page size than
the grant (i.e other than 4KB), the grant will always be mapped on the
first 4KB of each Linux page which make the final ring not contiguous in
the memory.
This can be fixed by mapping multiple grant in a same Linux page.
Signed-off-by: Julien Grall <julien.grall@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 89bf4b4e4a8d9ab219cd03aada24e782cf0ac359) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Julien Grall [Tue, 13 Oct 2015 16:50:12 +0000 (17:50 +0100)]
xen/grant-table: Add an helper to iterate over a specific number of grants
With the 64KB page granularity support on ARM64, a Linux page may be
split accross multiple grant.
Currently we have the helper gnttab_foreach_grant_in_grant to break a
Linux page based on an offset and a len, but it doesn't fit when we only
have a number of grants in hand.
Introduce a new helper which take an array of Linux page and a number of
grant and will figure out the address of each grant.
Signed-off-by: Julien Grall <julien.grall@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit f73314b28148f9ee9f89a0ae961c8fb36e3269fa) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Julien Grall [Wed, 7 Oct 2015 13:04:33 +0000 (14:04 +0100)]
xen/balloon: Use the correct sizeof when declaring frame_list
The type of the item in frame_list is xen_pfn_t which is not an unsigned
long on ARM but an uint64_t.
With the current computation, the size of frame_list will be 2 *
PAGE_SIZE rather than PAGE_SIZE.
I bet it's just mistake when the type has been switched from "unsigned
long" to "xen_pfn_t" in commit 965c0aaafe3e75d4e65cd4ec862915869bde3abd
"xen: balloon: use correct type for frame_list".
Signed-off-by: Julien Grall <julien.grall@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 3990dd27034606312429a09c807ea74a6ec32dde) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
xen/swiotlb: Add support for 64KB page granularity
Swiotlb is used on ARM64 to support DMA on platform where devices are
not protected by an SMMU. Furthermore it's only enabled for DOM0.
While Xen is always using 4KB page granularity in the stage-2 page table,
Linux ARM64 may either use 4KB or 64KB. This means that a Linux page
can be spanned accross multiple Xen page.
The Swiotlb code has to validate that the buffer used for DMA is
physically contiguous in the memory. As a Linux page can't be shared
between local memory and foreign page by design (the balloon code always
removing entirely a Linux page), the changes in the code are very
minimal because we only need to check the first Xen PFN.
Note that it may be possible to optimize the function
check_page_physically_contiguous to avoid looping over every Xen PFN
for local memory. Although I will let this optimization for a follow-up.
Julien Grall [Tue, 5 May 2015 15:36:56 +0000 (16:36 +0100)]
arm/xen: Add support for 64KB page granularity
The hypercall interface is always using 4KB page granularity. This is
requiring to use xen page definition macro when we deal with hypercall.
Note that pfn_to_gfn is working with a Xen pfn (i.e 4KB). We may want to
rename pfn_gfn to make this explicit.
We also allocate a 64KB page for the shared page even though only the
first 4KB is used. I don't think this is really important for now as it
helps to have the pointer 4KB aligned (XENMEM_add_to_physmap is taking a
Xen PFN).
Julien Grall [Tue, 5 May 2015 15:54:12 +0000 (16:54 +0100)]
xen/privcmd: Add support for Linux 64KB page granularity
The hypercall interface (as well as the toolstack) is always using 4KB
page granularity. When the toolstack is asking for mapping a series of
guest PFN in a batch, it expects to have the page map contiguously in
its virtual memory.
When Linux is using 64KB page granularity, the privcmd driver will have
to map multiple Xen PFN in a single Linux page.
Note that this solution works on page granularity which is a multiple of
4KB.
Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 5995a68a6272e4e8f4fe4de82cdc877e650fe8be) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Julien Grall [Tue, 5 May 2015 12:15:29 +0000 (13:15 +0100)]
net/xen-netback: Make it running on 64KB page granularity
The PV network protocol is using 4KB page granularity. The goal of this
patch is to allow a Linux using 64KB page granularity working as a
network backend on a non-modified Xen.
It's only necessary to adapt the ring size and break skb data in small
chunk of 4KB. The rest of the code is relying on the grant table code.
Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit d0089e8a0e4c9723d85b01713671358e3d6960df) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
net/xen-netfront: Make it running on 64KB page granularity
The PV network protocol is using 4KB page granularity. The goal of this
patch is to allow a Linux using 64KB page granularity using network
device on a non-modified Xen.
It's only necessary to adapt the ring size and break skb data in small
chunk of 4KB. The rest of the code is relying on the grant table code.
Note that we allocate a Linux page for each rx skb but only the first
4KB is used. We may improve the memory usage by extending the size of
the rx skb.
Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 30c5d7f0da82f55c86c0a09bf21c0623474bb17f) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Julien Grall [Tue, 5 May 2015 15:25:56 +0000 (16:25 +0100)]
block/xen-blkback: Make it running on 64KB page granularity
The PV block protocol is using 4KB page granularity. The goal of this
patch is to allow a Linux using 64KB page granularity behaving as a
block backend on a non-modified Xen.
It's only necessary to adapt the ring size and the number of request per
indirect frames. The rest of the code is relying on the grant table
code.
Note that the grant table code is allocating a Linux page per grant
which will result to waste 6OKB for every grant when Linux is using 64KB
page granularity. This could be improved by sharing the page between
multiple grants.
block/xen-blkfront: Make it running on 64KB page granularity
The PV block protocol is using 4KB page granularity. The goal of this
patch is to allow a Linux using 64KB page granularity using block
device on a non-modified Xen.
The block API is using segment which should at least be the size of a
Linux page. Therefore, the driver will have to break the page in chunk
of 4K before giving the page to the backend.
When breaking a 64KB segment in 4KB chunks, it is possible that some
chunks are empty. As the PV protocol always require to have data in the
chunk, we have to count the number of Xen page which will be in use and
avoid sending empty chunks.
Note that, a pre-defined number of grants are reserved before preparing
the request. This pre-defined number is based on the number and the
maximum size of the segments. If each segment contains a very small
amount of data, the driver may reserve too many grants (16 grants is
reserved per segment with 64KB page granularity).
Furthermore, in the case of persistent grants we allocate one Linux page
per grant although only the first 4KB of the page will be effectively
in use. This could be improved by sharing the page with multiple grants.
Signed-off-by: Julien Grall <julien.grall@citrix.com> Acked-by: Roger Pau Monné <roger.pau@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit c004a6fe0c405e2aa91b2a88aa1428724e6d06f6) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Julien Grall [Tue, 5 May 2015 15:37:30 +0000 (16:37 +0100)]
xen/events: fifo: Make it running on 64KB granularity
Only use the first 4KB of the page to store the events channel info. It
means that we will waste 60KB every time we allocate page for:
* control block: a page is allocating per CPU
* event array: a page is allocating everytime we need to expand it
I think we can reduce the memory waste for the 2 areas by:
* control block: sharing between multiple vCPUs. Although it will
require some bookkeeping in order to not free the page when the CPU
goes offline and the other CPUs sharing the page still there
* event array: always extend the array event by 64K (i.e 16 4K
chunk). That would require more care when we fail to expand the
event channel.
Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit a001c9d95c4ea96589461d58e77c96416a303e2c) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Julien Grall [Mon, 4 May 2015 14:39:08 +0000 (15:39 +0100)]
xen/balloon: Don't rely on the page granularity is the same for Xen and Linux
For ARM64 guests, Linux is able to support either 64K or 4K page
granularity. Although, the hypercall interface is always based on 4K
page granularity.
With 64K page granularity, a single page will be spread over multiple
Xen frame.
To avoid splitting the page into 4K frame, take advantage of the
extent_order field to directly allocate/free chunk of the Linux page
size.
Note that PVMMU is only used for PV guest (which is x86) and the page
granularity is always 4KB. Some BUILD_BUG_ON has been added to ensure
that because the code has not been modified.
Julien Grall [Mon, 11 May 2015 12:44:21 +0000 (13:44 +0100)]
xen/biomerge: Don't allow biovec's to be merged when Linux is not using 4KB pages
On ARM all dma-capable devices on a same platform may not be protected
by an IOMMU. The DMA requests have to use the BFN (i.e MFN on ARM) in
order to use correctly the device.
While the DOM0 memory is allocated in a 1:1 fashion (PFN == MFN), grant
mapping will screw this contiguous mapping.
When Linux is using 64KB page granularitary, the page may be split
accross multiple non-contiguous MFN (Xen is using 4KB page
granularity). Therefore a DMA request will likely fail.
Checking that a 64KB page is using contiguous MFN is tedious. For
now, always says that biovec are not mergeable.
Prepare the code to support 64KB page granularity. The first
implementation will use a full Linux page per indirect and persistent
grant. When non-persistent grant is used, each page of a bio request
may be split in multiple grant.
Furthermore, the field page of the grant structure is only used to copy
data from persistent grant or indirect grant. Avoid to set it for other
use case as it will have no meaning given the page will be split in
multiple grant.
Provide 2 functions, to setup indirect grant, the other for bio page.
Signed-off-by: Julien Grall <julien.grall@citrix.com> Acked-by: Roger Pau Monné <roger.pau@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 4f503fbdf319e4411aa48852b8922c93a9cc0c5d) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
pfn = page_to_gfn(...) /* Or similar */
gnttab_grant_foreign_access_ref
Replace it by a new helper. Note that when Linux is using a different
page granularity than Xen, the helper only gives access to the first 4KB
grant.
This is useful where drivers are allocating a full Linux page for each
grant.
Also include xen/interface/grant_table.h rather than xen/grant_table.h in
asm/page.h for x86 to fix a compilation issue [1]. Only the former is
useful in order to get the structure definition.
[1] Interdependency between asm/page.h and xen/grant_table.h which result
to page_mfn not being defined when necessary.
Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 3922f32c1e6db2e096ff095a5b8af0b940b97508) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Julien Grall [Fri, 19 Jun 2015 16:49:03 +0000 (17:49 +0100)]
xen/grant: Introduce helpers to split a page into grant
Currently, a grant is always based on the Xen page granularity (i.e
4KB). When Linux is using a different page granularity, a single page
will be split between multiple grants.
The new helpers will be in charge of splitting the Linux page into grants
and call a function given by the caller on each grant.
Also provide an helper to count the number of grants within a given
contiguous region.
Note that the x86/include/asm/xen/page.h is now including
xen/interface/grant_table.h rather than xen/grant_table.h. It's
necessary because xen/grant_table.h depends on asm/xen/page.h and will
break the compilation. Furthermore, only definition in
interface/grant_table.h is required.
Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 008c320a96d218712043f8db0111d5472697785c) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
David Vrabel [Wed, 22 Jul 2015 13:50:37 +0000 (14:50 +0100)]
xen/balloon: pre-allocate p2m entries for ballooned pages
Pages returned by alloc_xenballooned_pages() will be used for grant
mapping which will call set_phys_to_machine() (in PV guests).
Ballooned pages are set as INVALID_P2M_ENTRY in the p2m and thus may
be using the (shared) missing tables and a subsequent
set_phys_to_machine() will need to allocate new tables.
Since the grant mapping may be done from a context that cannot sleep,
the p2m entries must already be allocated.
Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
(cherry picked from commit 4a69c909deb0dd3cae653d14ac0ff52d5440a19c) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
David Vrabel [Wed, 22 Jul 2015 13:48:09 +0000 (14:48 +0100)]
x86/xen: export xen_alloc_p2m_entry()
Rename alloc_p2m() to xen_alloc_p2m_entry() and export it.
This is useful for ensuring that a p2m entry is allocated (i.e., not a
shared missing or identity entry) so that subsequent set_phys_to_machine()
calls will require no further allocations.
Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
v3:
- Make xen_alloc_p2m_entry() a nop on auto-xlate guests.
David Vrabel [Thu, 25 Jun 2015 15:29:18 +0000 (16:29 +0100)]
xen/balloon: use hotplugged pages for foreign mappings etc.
alloc_xenballooned_pages() is used to get ballooned pages to back
foreign mappings etc. Instead of having to balloon out real pages,
use (if supported) hotplugged memory.
This makes more memory available to the guest and reduces
fragmentation in the p2m.
This is only enabled if the xen.balloon.hotplug_unpopulated sysctl is
set to 1. This sysctl defaults to 0 in case the udev rules to
automatically online hotplugged memory do not exist.
Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
v3:
- Add xen.balloon.hotplug_unpopulated sysctl to enable use of hotplug
for unpopulated pages.
David Vrabel [Thu, 25 Jun 2015 11:10:28 +0000 (12:10 +0100)]
xen/balloon: only hotplug additional memory if required
Now that we track the total number of pages (included hotplugged
regions), it is easy to determine if more memory needs to be
hotplugged.
Add a new BP_WAIT state to signal that the balloon process needs to
wait until kicked by the memory add notifier (when the new section is
onlined by userspace).
Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
v3:
- Return BP_WAIT if enough sections are already hotplugged.
v2:
- New BP_WAIT status after adding new memory sections.
David Vrabel [Thu, 25 Jun 2015 11:08:20 +0000 (12:08 +0100)]
xen/balloon: rationalize memory hotplug stats
The stats used for memory hotplug make no sense and are fiddled with
in odd ways. Remove them and introduce total_pages to track the total
number of pages (both populated and unpopulated) including those within
hotplugged regions (note that this includes not yet onlined pages).
This will be used in a subsequent commit (xen/balloon: only hotplug
additional memory if required) when deciding whether additional memory
needs to be hotplugged.
Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
(cherry picked from commit de5a77d8422fc7ed0b2f4349bceb65a1a639e5b2) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
David Vrabel [Wed, 24 Jun 2015 14:58:42 +0000 (15:58 +0100)]
xen/balloon: find non-conflicting regions to place hotplugged memory
Instead of placing hotplugged memory at the end of RAM (which may
conflict with PCI devices or reserved regions) use allocate_resource()
to get a new, suitably aligned resource that does not conflict.
Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
v3:
- Remove stale comment.
David Vrabel [Mon, 19 Jan 2015 11:08:05 +0000 (11:08 +0000)]
x86/xen: discard RAM regions above the maximum reservation
During setup, discard RAM regions that are above the maximum
reservation (instead of marking them as E820_UNUSABLE). This allows
hotplug memory to be placed at these addresses.
Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
(cherry picked from commit f5775e0b6116b7e2425ccf535243b21768566d87) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
David Vrabel [Thu, 25 Jun 2015 12:18:12 +0000 (13:18 +0100)]
xen/balloon: remove scratch page left overs
Commit 0bb599fd30108883b00c7d4a226eeb49111e6932 (xen: remove scratch
frames for ballooned pages and m2p override) removed the use of the
scratch page for ballooned out pages.
Remove some left over function definitions.
Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
(cherry picked from commit f6a6cb1afe74d6ccc81aa70aa4ac3953762e7e6e) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
David Vrabel [Thu, 25 Jun 2015 15:35:49 +0000 (16:35 +0100)]
mm: memory hotplug with an existing resource
Add add_memory_resource() to add memory using an existing "System RAM"
resource. This is useful if the memory region is being located by
finding a free resource slot with allocate_resource().
Xen guests will make use of this in their balloon driver to hotplug
arbitrary amounts of memory in response to toolstack requests.
Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com> Reviewed-by: Tang Chen <tangchen@cn.fujitsu.com>
Conflicts:
include/linux/memory_hotplug.h
mm/memory_hotplug.c
chas williams [Wed, 16 Sep 2015 20:28:25 +0000 (16:28 -0400)]
xen-netfront: always set num queues if possible
If netfront connects with two (or more) queues and then reconnects with
only one queue it fails to delete or rewrite the multi-queue-num-queues
key and netback will try to use the wrong number of queues.
Always write the num-queues field if the backend has multi-queue support.
Signed-off-by: Chas Williams <3chas3@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 812494d9a0cacf77e0a538be18183c7b471812aa) Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Joao Martins [Sat, 26 Mar 2016 23:44:02 +0000 (23:44 +0000)]
Merge branch 'uek4/4.3-xen-backport' of git://ca-git.us.oracle.com/linux-konrad-public into linux-4.1/4.4-xen-backport
* uek4/4.3-xen-backport of git://ca-git.us.oracle.com/linux-konrad-public: (100 commits)
xen-netback: correctly check failed allocation
xen/blkback: free requests on disconnection
x86/xen/p2m: hint at the last populated P2M entry
x86/xen: Do not clip xen_e820_map to xen_e820_map_entries when sanitizing map
x86/xen: Support kexec/kdump in HVM guests by doing a soft reset
xen/x86: Don't try to write syscall-related MSRs for PV guests
xen: use correct type for HYPERVISOR_memory_op()
xen/xenbus: Rename the variable xen_store_mfn to xen_store_gfn
xen/privcmd: Further s/MFN/GFN/ clean-up
hvc/xen: Further s/MFN/GFN clean-up
video/xen-fbfront: Further s/MFN/GFN clean-up
xen/tmem: Use xen_page_to_gfn rather than pfn_to_gfn
xen: Use correctly the Xen memory terminologies
arm/xen: implement correctly pfn_to_mfn
xen: Make clear that swiotlb and biomerge are dealing with DMA address
xen: switch extra memory accounting to use pfns
xen: limit memory to architectural maximum
xen: avoid another early crash of memory limited dom0
xen: avoid early crash of memory limited dom0
arm/xen: Remove helpers which are PV specific
...
Insu Yun [Thu, 15 Oct 2015 18:02:28 +0000 (18:02 +0000)]
xen-netback: correctly check failed allocation
Since vzalloc can be failed in memory pressure,
writes -ENOMEM to xenstore to indicate error.
Signed-off-by: Insu Yun <wuninsu@gmail.com> Acked-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 833b8f18adfcca04070a8a42d545a4553379d36f) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Request allocation has been moved to connect_ring, which is called every
time blkback connects to the frontend (this can happen multiple times during
a blkback instance life cycle). On the other hand, request freeing has not
been moved, so it's only called when destroying the backend instance. Due to
this mismatch, blkback can allocate the request pool multiple times, without
freeing it.
In order to fix it, move the freeing of requests to xen_blkif_disconnect to
restore the symmetry between request allocation and freeing.
Reported-by: Julien Grall <julien.grall@citrix.com> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Tested-by: Julien Grall <julien.grall@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: xen-devel@lists.xenproject.org CC: stable@vger.kernel.org # 4.2 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
(cherry picked from commit f929d42ceb18a8acfd47e0e7b7d90b5d49bd9258) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
David Vrabel [Mon, 7 Sep 2015 16:14:08 +0000 (17:14 +0100)]
x86/xen/p2m: hint at the last populated P2M entry
With commit 633d6f17cd91ad5bf2370265946f716e42d388c6 (x86/xen: prepare
p2m list for memory hotplug) the P2M may be sized to accomdate a much
larger amount of memory than the domain currently has.
When saving a domain, the toolstack must scan all the P2M looking for
populated pages. This results in a performance regression due to the
unnecessary scanning.
Instead of reporting (via shared_info) the maximum possible size of
the P2M, hint at the last PFN which might be populated. This hint is
increased as new leaves are added to the P2M (in the expectation that
they will be used for populated entries).
Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: <stable@vger.kernel.org> # 4.0+
(cherry picked from commit 98dd166ea3a3c3b57919e20d9b0d1237fcd0349d) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
x86/xen: Do not clip xen_e820_map to xen_e820_map_entries when sanitizing map
Sanitizing the e820 map may produce extra E820 entries which would result in
the topmost E820 entries being removed. The removed entries would typically
include the top E820 usable RAM region and thus result in the domain having
signicantly less RAM available to it.
Fix by allowing sanitize_e820_map to use the full size of the allocated E820
array.
Signed-off-by: Malcolm Crossley <malcolm.crossley@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 64c98e7f49100b637cd20a6c63508caed6bbba7a) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
x86/xen: Support kexec/kdump in HVM guests by doing a soft reset
Currently there is a number of issues preventing PVHVM Xen guests from
doing successful kexec/kdump:
- Bound event channels.
- Registered vcpu_info.
- PIRQ/emuirq mappings.
- shared_info frame after XENMAPSPACE_shared_info operation.
- Active grant mappings.
Basically, newly booted kernel stumbles upon already set up Xen
interfaces and there is no way to reestablish them. In Xen-4.7 a new
feature called 'soft reset' is coming. A guest performing kexec/kdump
operation is supposed to call SCHEDOP_shutdown hypercall with
SHUTDOWN_soft_reset reason before jumping to new kernel. Hypervisor
(with some help from toolstack) will do full domain cleanup (but
keeping its memory and vCPU contexts intact) returning the guest to
the state it had when it was first booted and thus allowing it to
start over.
Doing SHUTDOWN_soft_reset on Xen hypervisors which don't support it is
probably OK as by default all unknown shutdown reasons cause domain
destroy with a message in toolstack log: 'Unknown shutdown reason code
5. Destroying domain.' which gives a clue to what the problem is and
eliminates false expectations.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 0b34a166f291d255755be46e43ed5497cdd194f2) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Boris Ostrovsky [Mon, 21 Sep 2015 13:09:28 +0000 (09:09 -0400)]
xen/x86: Don't try to write syscall-related MSRs for PV guests
For PV guests these registers are set up by hypervisor and thus
should not be written by the guest. The comment in xen_write_msr_safe()
says so but we still write the MSRs, causing the hypervisor to
print a warning.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 2ecf91b6d8b0ee8ef38aa7ea2a0fe0cd57b6ca50) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
HYPERVISOR_memory_op() is defined to return an "int" value. This is
wrong, as the Xen hypervisor will return "long".
The sub-function XENMEM_maximum_reservation returns the maximum
number of pages for the current domain. An int will overflow for a
domain configured with 8TB of memory or more.
Correct this by using the correct type.
Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 24f775a6605a8ffc697c0767fc7ea85656ddb958) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Julien Grall [Fri, 7 Aug 2015 16:34:41 +0000 (17:34 +0100)]
xen/privcmd: Further s/MFN/GFN/ clean-up
The privcmd code is mixing the usage of GFN and MFN within the same
functions which make the code difficult to understand when you only work
with auto-translated guests.
The privcmd driver is only dealing with GFN so replace all the mention
of MFN into GFN.
The ioctl structure used to map foreign change has been left unchanged
given that the userspace is using it. Nonetheless, add a comment to
explain the expected value within the "mfn" field.
Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit a13d7201d7deedcbb6ac6efa94a1a7d34d3d79ec) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Julien Grall [Fri, 7 Aug 2015 16:34:37 +0000 (17:34 +0100)]
xen: Use correctly the Xen memory terminologies
Based on include/xen/mm.h [1], Linux is mistakenly using MFN when GFN
is meant, I suspect this is because the first support for Xen was for
PV. This resulted in some misimplementation of helpers on ARM and
confused developers about the expected behavior.
For instance, with pfn_to_mfn, we expect to get an MFN based on the name.
Although, if we look at the implementation on x86, it's returning a GFN.
For clarity and avoid new confusion, replace any reference to mfn with
gfn in any helpers used by PV drivers. The x86 code will still keep some
reference of pfn_to_mfn which may be used by all kind of guests
No changes as been made in the hypercall field, even
though they may be invalid, in order to keep the same as the defintion
in xen repo.
Note that page_to_mfn has been renamed to xen_page_to_gfn to avoid a
name to close to the KVM function gfn_to_page.
Take also the opportunity to simplify simple construction such
as pfn_to_mfn(page_to_pfn(page)) into xen_page_to_gfn. More complex clean up
will come in follow-up patches.
Julien Grall [Fri, 7 Aug 2015 16:34:36 +0000 (17:34 +0100)]
arm/xen: implement correctly pfn_to_mfn
After the commit introducing convertion between DMA and guest addresses,
all the callers of pfn_to_mfn are expecting to get a GFN (Guest Frame
Number). On ARM, all the guests are auto-translated so the GFN is equal
to the Linux PFN (Pseudo-physical Frame Number).
The current implementation may return an MFN if the caller is passing a
PFN associated to a mapped foreign grant. In pratice, I haven't seen
the problem on running guest but we should fix it for the sake of
correctness.
Correct the implementation by always returning the pfn passed in parameter.
A follow-up patch will take care to rename pfn_to_mfn to a suitable
name.
Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 5192b35de47e47a0f736fe30da199f32030680e7) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Julien Grall [Fri, 7 Aug 2015 16:34:35 +0000 (17:34 +0100)]
xen: Make clear that swiotlb and biomerge are dealing with DMA address
The swiotlb is required when programming a DMA address on ARM when a
device is not protected by an IOMMU.
In this case, the DMA address should always be equal to the machine address.
For DOM0 memory, Xen ensure it by have an identity mapping between the
guest address and host address. However, when mapping a foreign grant
reference, the 1:1 model doesn't work.
For ARM guest, most of the callers of pfn_to_mfn expects to get a GFN
(Guest Frame Number), i.e a PFN (Page Frame Number) from the Linux point
of view given that all ARM guest are auto-translated.
Even though the name pfn_to_mfn is misleading, we need to ensure that
those caller get a GFN and not by mistake a MFN. In pratical, I haven't
seen error related to this but we should fix it for the sake of
correctness.
In order to fix the implementation of pfn_to_mfn on ARM in a follow-up
patch, we have to introduce new helpers to return the DMA from a PFN and
the invert.
On x86, the new helpers will be an alias of pfn_to_mfn and mfn_to_pfn.
The helpers will be used in swiotlb and xen_biovec_phys_mergeable.
This is necessary in the latter because we have to ensure that the
biovec code will not try to merge a biovec using foreign page and
another using Linux memory.
Lastly, the helper mfn_to_local_pfn has been renamed to bfn_to_local_pfn
given that the only usage was in swiotlb.
Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 32e09870eedfb501a6cb5729d8c23f44f8a7cbdd) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Instead of using physical addresses for accounting of extra memory
areas available for ballooning switch to pfns as this is much less
error prone regarding partial pages.
Reported-by: Roger Pau Monné <roger.pau@citrix.com> Tested-by: Roger Pau Monné <roger.pau@citrix.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 626d7508664c4bc8e67f496da4387ecd0c410b8c) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When a pv-domain (including dom0) is started it tries to size it's
p2m list according to the maximum possible memory amount it ever can
achieve. Limit the initial maximum memory size to the architectural
limit of the hardware in order to avoid overflows during remapping
of memory.
This problem will occur when dom0 is started with an initial memory
size being a multiple of 1GB, but without specifying it's maximum
memory size. The kernel must be configured without
CONFIG_XEN_BALLOON_MEMORY_HOTPLUG for the problem to happen.
Reported-by: Roger Pau Monné <roger.pau@citrix.com> Tested-by: Roger Pau Monné <roger.pau@citrix.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit cb9e444b5aaa900bb4310da411315b6947c53e37) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Juergen Gross [Wed, 19 Aug 2015 16:53:11 +0000 (18:53 +0200)]
xen: avoid another early crash of memory limited dom0
Commit b1c9f169047b ("xen: split counting of extra memory pages...")
introduced an error when dom0 was started with limited memory occurring
only on some hardware.
The problem arises in case dom0 is started with initial memory and
maximum memory being the same. The kernel must be configured without
CONFIG_XEN_BALLOON_MEMORY_HOTPLUG for the problem to happen. If all
of this is true and the E820 map of the machine is sparse (some areas
are not covered) then the machine might crash early in the boot
process.
An example E820 map triggering the problem looks like this:
In this case the area a0000-dffff isn't present in the map. This will
confuse the memory setup of the domain when remapping the memory from
such holes to populated areas.
To avoid the problem the accounting of to be remapped memory has to
count such holes in the E820 map as well.
Reported-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit ab24507cfae8d916814bb6c16f66e453184a29a5) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Juergen Gross [Wed, 19 Aug 2015 16:52:34 +0000 (18:52 +0200)]
xen: avoid early crash of memory limited dom0
Commit b1c9f169047b ("xen: split counting of extra memory pages...")
introduced an error when dom0 was started with limited memory.
The problem arises in case dom0 is started with initial memory and
maximum memory being the same and exactly a multiple of 1 GB. The
kernel must be configured without CONFIG_XEN_BALLOON_MEMORY_HOTPLUG
for the problem to happen. In this case it will crash very early
during boot due to the virtual mapped p2m list not being large
enough to be able to remap any memory:
This can be avoided by allocating aneough space for the p2m to cover
the maximum memory of dom0 plus the identity mapped holes required
for PCI space, BIOS etc.
Reported-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit eafd72e016c69df511b14a98b61e439c58ad9c51) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Boris Ostrovsky [Mon, 10 Aug 2015 20:34:38 +0000 (16:34 -0400)]
xen/x86: Don't try to set PCE bit in CR4
Since VPMU code emulates RDPMC instruction with RDMSR and because hypervisor
does not emulate it there is no reason to try setting CR4's PCE bit (and the
hypervisor will warn on seeing it set).
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 3375d8284dfb7866f261ec008d15d30999ff273b) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Boris Ostrovsky [Mon, 10 Aug 2015 20:34:37 +0000 (16:34 -0400)]
xen/PMU: PMU emulation code
Add PMU emulation code that runs when we are processing a PMU interrupt.
This code will allow us not to trap to hypervisor on each MSR/LVTPC access
(of which there may be quite a few in the handler).
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit bf6dfb154d935725c9a2005033ca33017b9df439) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Boris Ostrovsky [Mon, 10 Aug 2015 20:34:36 +0000 (16:34 -0400)]
xen/PMU: Intercept PMU-related MSR and APIC accesses
Provide interfaces for recognizing accesses to PMU-related MSRs and
LVTPC APIC and process these accesses in Xen PMU code.
(The interrupt handler performs XENPMU_flush right away in the beginning
since no PMU emulation is available. It will be added with a later patch).
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 6b08cd6328c58a2ae190c5ee03a2ffcab5ef828e) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Boris Ostrovsky [Mon, 10 Aug 2015 20:34:35 +0000 (16:34 -0400)]
xen/PMU: Describe vendor-specific PMU registers
AMD and Intel PMU register initialization and helpers that determine
whether a register belongs to PMU.
This and some of subsequent PMU emulation code is somewhat similar to
Xen's PMU implementation.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit e27b72df01109c689062caeba1defa013b759e0e) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Boris Ostrovsky [Mon, 10 Aug 2015 20:34:34 +0000 (16:34 -0400)]
xen/PMU: Initialization code for Xen PMU
Map shared data structure that will hold CPU registers, VPMU context,
V/PCPU IDs of the CPU interrupted by PMU interrupt. Hypervisor fills
this information in its handler and passes it to the guest for further
processing.
Set up PMU VIRQ.
Now that perf infrastructure will assume that PMU is available on a PV
guest we need to be careful and make sure that accesses via RDPMC
instruction don't cause fatal traps by the hypervisor. Provide a nop
RDPMC handler.
For the same reason avoid issuing a warning on a write to APIC's LVTPC.
Both of these will be made functional in later patches.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 65d0cf0be79feebeb19e7626fd3ed41ae73f642d) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Boris Ostrovsky [Mon, 10 Aug 2015 20:34:33 +0000 (16:34 -0400)]
xen/PMU: Sysfs interface for setting Xen PMU mode
Set Xen's PMU mode via /sys/hypervisor/pmu/pmu_mode. Add XENPMU hypercall.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 5f141548824cebbff2e838ff401c34e667797467) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Boris Ostrovsky [Mon, 10 Aug 2015 20:34:32 +0000 (16:34 -0400)]
xen: xensyms support
Export Xen symbols to dom0 via /proc/xen/xensyms (similar to
/proc/kallsyms).
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit a11f4f0a4e18b4bdc7d5e36438711e038b7a1f74) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen: allow more than 512 GB of RAM for 64 bit pv-domains
64 bit pv-domains under Xen are limited to 512 GB of RAM today. The
main reason has been the 3 level p2m tree, which was replaced by the
virtual mapped linear p2m list. Parallel to the p2m list which is
being used by the kernel itself there is a 3 level mfn tree for usage
by the Xen tools and eventually for crash dump analysis. For this tree
the linear p2m list can serve as a replacement, too. As the kernel
can't know whether the tools are capable of dealing with the p2m list
instead of the mfn tree, the limit of 512 GB can't be dropped in all
cases.
This patch replaces the hard limit by a kernel parameter which tells
the kernel to obey the 512 GB limit or not. The default is selected by
a configuration parameter which specifies whether the 512 GB limit
should be active per default for domUs (domain save/restore/migration
and crash dump analysis are affected).
Memory above the domain limit is returned to the hypervisor instead of
being identity mapped, which was wrong anyway.
The kernel configuration parameter to specify the maximum size of a
domain can be deleted, as it is not relevant any more.
Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit c70727a5bc18a5a233fddc6056d1de9144d7a293) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Check whether the hypervisor supplied p2m list is placed at a location
which is conflicting with the target E820 map. If this is the case
relocate it to a new area unused up to now and compliant to the E820
map.
As the p2m list might by huge (up to several GB) and is required to be
mapped virtually, set up a temporary mapping for the copied list.
For pvh domains just delete the p2m related information from start
info instead of reserving the p2m memory, as we don't need it at all.
For 32 bit kernels adjust the memblock_reserve() parameters in order
to cover the page tables only. This requires to memblock_reserve() the
start_info page on it's own.
Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 70e61199559a09c62714694cd5ac3c3640c41552) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen: add explicit memblock_reserve() calls for special pages
Some special pages containing interfaces to xen are being reserved
implicitly only today. The memblock_reserve() call to reserve them is
meant to reserve the p2m list supplied by xen. It is just reserving
not only the p2m list itself, but some more pages up to the start of
the xen built page tables.
To be able to move the p2m list to another pfn range, which is needed
for support of huge RAM, this memblock_reserve() must be split up to
cover all affected reserved pages explicitly.
The affected pages are:
- start_info page
- xenstore ring (might be missing, mfn is 0 in this case)
- console ring (not for initial domain)
Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 6c2681c863b24360098d1ba60f2af060a13a0561) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
mm: provide early_memremap_ro to establish read-only mapping
During early boot as Xen pv domain the kernel needs to map some page
tables supplied by the hypervisor read only. This is needed to be
able to relocate some data structures conflicting with the physical
memory map especially on systems with huge RAM (above 512GB).
Provide the function early_memremap_ro() to provide this read only
mapping.
Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 2592dbbbf4c67501c2bd2dcf89c2b8924d592a9f) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Check whether the initrd is placed at a location which is conflicting
with the target E820 map. If this is the case relocate it to a new
area unused up to now and compliant to the E820 map.
Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 4b9c15377f96e241be347fd3bbeeff74fbad0b44) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen: check pre-allocated page tables for conflict with memory map
Check whether the page tables built by the domain builder are at
memory addresses which are in conflict with the target memory map.
If this is the case just panic instead of running into problems
later.
Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 04414baab5ba862b10bde837c4773ffdbb78f0e0) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen: check for kernel memory conflicting with memory layout
Checks whether the pre-allocated memory of the loaded kernel is in
conflict with the target memory map. If this is the case, just panic
instead of run into problems later, as there is nothing we can do
to repair this situation.
Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 808fdb71936c41d46245f0e3aa6ec889cba70d97) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
For being able to relocate pre-allocated data areas like initrd or
p2m list it is mandatory to find a contiguous memory area which is
not yet in use and doesn't conflict with the memory map we want to
be in effect.
In case such an area is found reserve it at once as this will be
required to be done in any case.
Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 9ddac5b724a9465e27f25a0aa943e92c8341a85b) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Provide a service routine to check a physical memory area against the
E820 map. The routine will return false if the complete area is RAM
according to the E820 map and true otherwise.
Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit e612b4a7db4ae1dd8c2bbe171e10c21723de95b2) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen: split counting of extra memory pages from remapping
Memory pages in the initial memory setup done by the Xen hypervisor
conflicting with the target E820 map are remapped. In order to do this
those pages are counted and remapped in xen_set_identity_and_remap().
Split the counting from the remapping operation to be able to setup
the needed memory sizes in time but doing the remap operation at a
later time. This enables us to simplify the interface to
xen_set_identity_and_remap() as the number of remapped and released
pages is no longer needed here.
Finally move the remapping further down to prepare relocating
conflicting memory contents before the memory might be clobbered by
xen_set_identity_and_remap(). This requires to not destroy the Xen
E820 map when the one for the system is being constructed.
Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 5097cdf6cef15439f971df54f9abcf143d7ca698) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Instead of using a function local static e820 map in xen_memory_setup()
and calling various functions in the same source with the map as a
parameter use a map directly accessible by all functions in the source.
Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 69632ecfcd03b12202ed62dfa0aabac83904f8ac) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen: eliminate scalability issues from initial mapping setup
Direct Xen to place the initial P->M table outside of the initial
mapping, as otherwise the 1G (implementation) / 2G (theoretical)
restriction on the size of the initial mapping limits the amount
of memory a domain can be handed initially.
As the initial P->M table is copied rather early during boot to
domain private memory and it's initial virtual mapping is dropped,
the easiest way to avoid virtual address conflicts with other
addresses in the kernel is to use a user address area for the
virtual address of the initial P->M table. This allows us to just
throw away the page tables of the initial mapping after the copy
without having to care about address invalidation.
It should be noted that this patch won't enable a pv-domain to USE
more than 512 GB of RAM. It just enables it to be started with a
P->M table covering more memory. This is especially important for
being able to boot a Dom0 on a system with more than 512 GB memory.
Signed-off-by: Juergen Gross <jgross@suse.com> Based-on-patch-by: Jan Beulich <jbeulich@suse.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 8f5b0c63987207fd5c3c1f89c9eb6cb95b30386e) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen: save linear p2m list address in shared info structure
The virtual address of the linear p2m list should be stored in the
shared info structure read by the Xen tools to be able to support
64 bit pv-domains larger than 512 GB. Additionally the linear p2m
list interface includes a generation count which is changed prior
to and after each mapping change of the p2m list. Reading the
generation count the Xen tools can detect changes of the mappings
and re-read the p2m list eventually.
Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 4b9c9a11803eaa73b3223da9fcaea39b2f919d80) Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
projects / users / jedix / linux-maple.git / log