aboutsummaryrefslogtreecommitdiffstats
path: root/arch/s390/kvm/guestdbg.c
AgeCommit message (Collapse)Author
2016-07-05KVM: s390: inject PER i-fetch events on applicable icptsDavid Hildenbrand
In case we have to emuluate an instruction or part of it (instruction, partial instruction, operation exception), we have to inject a PER instruction-fetching event for that instruction, if hardware told us to do so. In case we retry an instruction, we must not inject the PER event. Please note that we don't filter the events properly yet, so guest debugging will be visible for the guest. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-14KVM: S390: Fix typoAndrea Gelmini
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-08s390: Fix misspellings in commentsAdam Buchbinder
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-19s390: remove all usages of PSW_ADDR_INSNHeiko Carstens
Yet another leftover from the 31 bit era. The usual operation "y = x & PSW_ADDR_INSN" with the PSW_ADDR_INSN mask is a nop for CONFIG_64BIT. Therefore remove all usages and hope the code is a bit less confusing. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
2015-07-29KVM: s390: filter space-switch events when PER is enforcedDavid Hildenbrand
When guest debugging is active, space-switch events might be enforced by PER. While the PER events are correctly filtered out, space-switch-events could be forwarded to the guest, although from a guest point of view, they should not have been reported. Therefore we have to filter out space-switch events being concurrently reported with a PER event, if the PER event got filtered out. To do so, we theoretically have to know which instruction was responsible for the event. As the applicable instructions modify the PSW address, the address space set in the PSW and even the address space in cr1, we can't figure out the instruction that way. For this reason, we have to rely on the information about the old and new address space, in order to guess the responsible instruction type and do appropriate checks for space-switch events. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-06KVM: s390: Use the read_guest_abs() in guest debug functionsAlexander Yarygin
The guest debug functions work on absolute addresses and should use the read_guest_abs() function rather than general read_guest() that works with logical addresses. Cc: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2014-05-06KVM: s390: return -EFAULT if copy_from_user() failsDan Carpenter
When copy_from_user() fails, this code returns the number of bytes remaining instead of a negative error code. The positive number is returned to the user but otherwise it is harmless. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2014-04-22KVM: s390: no timer interrupts when single-stepping a guestDavid Hildenbrand
When a guest is single-stepped, we want to disable timer interrupts. Otherwise, the guest will continuously execute the external interrupt handler and make debugging of code where timer interrupts are enabled almost impossible. The delivery of timer interrupts can be enforced in such sections by setting a breakpoint and continuing execution. In order to disable timer interrupts, they are disabled in the control register of the guest just before SIE entry and are suppressed in the interrupt check/delivery methods. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2014-04-22KVM: s390: hardware support for guest debuggingDavid Hildenbrand
This patch adds support to debug the guest using the PER facility on s390. Single-stepping, hardware breakpoints and hardware watchpoints are supported. In order to use the PER facility of the guest without it noticing it, the control registers of the guest have to be patched and access to them has to be intercepted(stctl, stctg, lctl, lctlg). All PER program interrupts have to be intercepted and only the relevant PER interrupts for the guest have to be given back. Special care has to be taken about repeated exits on the same hardware breakpoint. The intervention of the host in the guests PER configuration is not fully transparent. PER instruction nullification can not be used by the guest and too many storage alteration events may be reported to the guest (if it is activated for special address ranges only) when the host concurrently debugging it. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>