kernel/linux.git/include/xen/interface, branch v4.1.25

x86/xen: Support kexec/kdump in HVM guests by doing a soft reset

2015-10-22T21:43:14+00:00

commit 0b34a166f291d255755be46e43ed5497cdd194f2 upstream. 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 Signed-off-by: David Vrabel Signed-off-by: Greg Kroah-Hartman

xen: synchronize include/xen/interface/xen.h with xen

2015-03-16T14:49:13+00:00

The header include/xen/interface/xen.h doesn't contain all definitions from Xen's version of that header. Update it accordingly. Signed-off-by: Juergen Gross Reviewed-by: David Vrabel Signed-off-by: David Vrabel

xen/gntdev: mark userspace PTEs as special on x86 PV guests

2015-01-28T14:04:21+00:00

In an x86 PV guest, get_user_pages_fast() on a userspace address range containing foreign mappings does not work correctly because the M2P lookup of the MFN from a userspace PTE may return the wrong page. Force get_user_pages_fast() to fail on such addresses by marking the PTEs as special. If Xen has XENFEAT_gnttab_map_avail_bits (available since at least 4.0), we can do so efficiently in the grant map hypercall. Otherwise, it needs to be done afterwards. This is both inefficient and racy (the mapping is visible to the task before we fixup the PTEs), but will be fine for well-behaved applications that do not use the mapping until after the mmap() system call returns. Guests with XENFEAT_auto_translated_physmap (ARM and x86 HVM or PVH) do not need this since get_user_pages() has always worked correctly for them. Signed-off-by: David Vrabel Reviewed-by: Stefano Stabellini

x86/xen: properly retrieve NMI reason

2015-01-13T09:39:50+00:00

Using the native code here can't work properly, as the hypervisor would normally have cleared the two reason bits by the time Dom0 gets to see the NMI (if passed to it at all). There's a shared info field for this, and there's an existing hook to use - just fit the two together. This is particularly relevant so that NMIs intended to be handled by APEI / GHES actually make it to the respective handler. Note that the hook can (and should) be used irrespective of whether being in Dom0, as accessing port 0x61 in a DomU would be even worse, while the shared info field would just hold zero all the time. Note further that hardware NMI handling for PVH doesn't currently work anyway due to missing code in the hypervisor (but it is expected to work the native rather than the PV way). Signed-off-by: Jan Beulich Reviewed-by: Boris Ostrovsky Signed-off-by: David Vrabel

xen/arm: introduce GNTTABOP_cache_flush

2014-12-04T12:41:54+00:00

Introduce support for new hypercall GNTTABOP_cache_flush. Use it to perform cache flashing on pages used for dma when necessary. If GNTTABOP_cache_flush is supported by the hypervisor, we don't need to bounce dma map operations that involve foreign grants and non-coherent devices. Signed-off-by: Stefano Stabellini Reviewed-by: Catalin Marinas Acked-by: Ian Campbell

xen/arm: remove handling of XENFEAT_grant_map_identity

2014-12-04T12:41:45+00:00

The feature has been removed from Xen. Also Linux cannot use it on ARM32 without CONFIG_ARM_LPAE. Signed-off-by: Stefano Stabellini Acked-by: Ian Campbell Reviewed-by: David Vrabel Reviewed-by: Catalin Marinas

xen: sync some headers with xen tree

2014-10-03T11:34:52+00:00

To be able to use an initially unmapped initrd with xen the following header files must be synced to a newer version from the xen tree: include/xen/interface/elfnote.h include/xen/interface/xen.h As the KEXEC and DUMPCORE related ELFNOTES are not relevant for the kernel they are omitted from elfnote.h. Signed-off-by: Juergen Gross Signed-off-by: David Vrabel

xen: Add Xen pvSCSI protocol description

2014-09-23T13:36:19+00:00

Add the definition of pvSCSI protocol used between the pvSCSI frontend in a XEN domU and the pvSCSI backend in a XEN driver domain (usually Dom0). This header was originally provided by Fujitsu for Xen based on Linux 2.6.18. Changes are: - Added comments. - Adapt to Linux style guide. - Add support for larger SG-lists by putting them in an own granted page. - Remove stale definitions. Signed-off-by: Juergen Gross Signed-off-by: David Vrabel

xen/arm: introduce XENFEAT_grant_map_identity

2014-09-11T18:11:52+00:00

The flag tells us that the hypervisor maps a grant page to guest physical address == machine address of the page in addition to the normal grant mapping address. It is needed to properly issue cache maintenance operation at the completion of a DMA operation involving a foreign grant. Signed-off-by: Stefano Stabellini Tested-by: Denis Schneider

xen: Define EFI related stuff

2014-07-18T20:23:57+00:00

Define constants and structures which are needed to properly execute EFI related hypercall in Xen dom0. This patch is based on Jan Beulich and Tang Liang work. Signed-off-by: Jan Beulich Signed-off-by: Tang Liang Signed-off-by: Daniel Kiper Reviewed-by: David Vrabel Acked-by: Stefano Stabellini Signed-off-by: Matt Fleming