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linux/drivers/xen/fallback.c

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xen/hypercall: fix hypercall fallback code for very old hypervisors While copying the argument structures in HYPERVISOR_event_channel_op() and HYPERVISOR_physdev_op() into the local variable is sufficiently safe even if the actual structure is smaller than the container one, copying back eventual output values the same way isn't: This may collide with on-stack variables (particularly "rc") which may change between the first and second memcpy() (i.e. the second memcpy() could discard that change). Move the fallback code into out-of-line functions, and handle all of the operations known by this old a hypervisor individually: Some don't require copying back anything at all, and for the rest use the individual argument structures' sizes rather than the container's. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jan Beulich <jbeulich@suse.com> [v2: Reduce #define/#undef usage in HYPERVISOR_physdev_op_compat().] [v3: Fix compile errors when modules use said hypercalls] [v4: Add xen_ prefix to the HYPERCALL_..] [v5: Alter the name and only EXPORT_SYMBOL_GPL one of them] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-19 15:25:37 -04:00
xen-pciback: notify hypervisor about devices intended to be assigned to guests For MSI-X capable devices the hypervisor wants to write protect the MSI-X table and PBA, yet it can't assume that resources have been assigned to their final values at device enumeration time. Thus have pciback do that notification, as having the device controlled by it is a prerequisite to assigning the device to guests anyway. This is the kernel part of hypervisor side commit 4245d33 ("x86/MSI: add mechanism to fully protect MSI-X table from PV guest accesses") on the master branch of git://xenbits.xen.org/xen.git. CC: stable@vger.kernel.org Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-03-12 15:06:23 +00:00
xen/hypercall: fix hypercall fallback code for very old hypervisors While copying the argument structures in HYPERVISOR_event_channel_op() and HYPERVISOR_physdev_op() into the local variable is sufficiently safe even if the actual structure is smaller than the container one, copying back eventual output values the same way isn't: This may collide with on-stack variables (particularly "rc") which may change between the first and second memcpy() (i.e. the second memcpy() could discard that change). Move the fallback code into out-of-line functions, and handle all of the operations known by this old a hypervisor individually: Some don't require copying back anything at all, and for the rest use the individual argument structures' sizes rather than the container's. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jan Beulich <jbeulich@suse.com> [v2: Reduce #define/#undef usage in HYPERVISOR_physdev_op_compat().] [v3: Fix compile errors when modules use said hypercalls] [v4: Add xen_ prefix to the HYPERCALL_..] [v5: Alter the name and only EXPORT_SYMBOL_GPL one of them] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-19 15:25:37 -04:00
xen-pciback: notify hypervisor about devices intended to be assigned to guests For MSI-X capable devices the hypervisor wants to write protect the MSI-X table and PBA, yet it can't assume that resources have been assigned to their final values at device enumeration time. Thus have pciback do that notification, as having the device controlled by it is a prerequisite to assigning the device to guests anyway. This is the kernel part of hypervisor side commit 4245d33 ("x86/MSI: add mechanism to fully protect MSI-X table from PV guest accesses") on the master branch of git://xenbits.xen.org/xen.git. CC: stable@vger.kernel.org Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-03-12 15:06:23 +00:00