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* MIPS: KVM: Remove redundant semicolonJames Hogan2014-05-30
| | | | | | | | | | | | | Remove extra semicolon in kvm_arch_vcpu_dump_regs(). Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Remove redundant NULL checks before kfree()James Hogan2014-05-30
| | | | | | | | | | | | | | The kfree() function already NULL checks the parameter so remove the redundant NULL checks before kfree() calls in arch/mips/kvm/. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Quieten kvm_info() loggingJames Hogan2014-05-30
| | | | | | | | | | | | | | | The logging from MIPS KVM is fairly noisy with kvm_info() in places where it shouldn't be, such as on VM creation and migration to a different CPU. Replace these kvm_info() calls with kvm_debug(). Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Remove ifdef DEBUG around kvm_debugJames Hogan2014-05-30
| | | | | | | | | | | | | | | | | | kvm_debug() uses pr_debug() which is already compiled out in the absence of a DEBUG define, so remove the unnecessary ifdef DEBUG lines around kvm_debug() calls which are littered around arch/mips/kvm/. As well as generally cleaning up, this prevents future bit-rot due to DEBUG not being commonly used. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Fix kvm_debug bit-rottageJames Hogan2014-05-30
| | | | | | | | | | | | | | | | | | | Fix build errors when DEBUG is defined in arch/mips/kvm/. - The DEBUG code in kvm_mips_handle_tlbmod() was missing some variables. - The DEBUG code in kvm_mips_host_tlb_write() was conditional on an undefined "debug" variable. - The DEBUG code in kvm_mips_host_tlb_inv() accessed asid_map directly rather than using kvm_mips_get_user_asid(). Also fixed brace placement. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Whitespace fixes in kvm_mips_callbacksJames Hogan2014-05-30
| | | | | | | | | | | | | Fix whitespace in struct kvm_mips_callbacks function pointers. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Make kvm_mips_comparecount_{func,wakeup} staticJames Hogan2014-05-30
| | | | | | | | | | | | | | | The kvm_mips_comparecount_func() and kvm_mips_comparecount_wakeup() functions are only used within arch/mips/kvm/kvm_mips.c, so make them static. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Add count frequency KVM registerJames Hogan2014-05-30
| | | | | | | | | | | | | | | | | | | Expose the KVM guest CP0_Count frequency to userland via a new KVM_REG_MIPS_COUNT_HZ register accessible with the KVM_{GET,SET}_ONE_REG ioctls. When the frequency is altered the bias is adjusted such that the guest CP0_Count doesn't jump discontinuously or lose any timer interrupts. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: David Daney <david.daney@cavium.com> Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Add master disable count interfaceJames Hogan2014-05-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Expose two new virtual registers to userland via the KVM_{GET,SET}_ONE_REG ioctls. KVM_REG_MIPS_COUNT_CTL is for timer configuration fields and just contains a master disable count bit. This can be used by userland to freeze the timer in order to read a consistent state from the timer count value and timer interrupt pending bit. This cannot be done with the CP0_Cause.DC bit because the timer interrupt pending bit (TI) is also in CP0_Cause so it would be impossible to stop the timer without also risking a race with an hrtimer interrupt and having to explicitly check whether an interrupt should have occurred. When the timer is re-enabled it resumes without losing time, i.e. the CP0_Count value jumps to what it would have been had the timer not been disabled, which would also be impossible to do from userland with CP0_Cause.DC. The timer interrupt also cannot be lost, i.e. if a timer interrupt would have occurred had the timer not been disabled it is queued when the timer is re-enabled. This works by storing the nanosecond monotonic time when the master disable is set, and using it for various operations instead of the current monotonic time (e.g. when recalculating the bias when the CP0_Count is set), until the master disable is cleared again, i.e. the timer state is read/written as it would have been at that time. This state is exposed to userland via the read-only KVM_REG_MIPS_COUNT_RESUME virtual register so that userland can determine the exact time the master disable took effect. This should allow userland to atomically save the state of the timer, and later restore it. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: David Daney <david.daney@cavium.com> Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Override guest kernel timer frequency directlyJames Hogan2014-05-30
| | | | | | | | | | | | | | | | | | | | | | | The KVM_HOST_FREQ Kconfig symbol was used by KVM guest kernels to override the timer frequency calculation to a value based on the host frequency. Now that the KVM timer emulation is implemented independent of the host timer frequency and defaults to 100MHz, adjust the working of CONFIG_KVM_HOST_FREQ to match. The Kconfig symbol now specifies the guest timer frequency directly, and has been renamed accordingly to KVM_GUEST_TIMER_FREQ. It now defaults to 100MHz too and the help text is updated to make it clear that a zero value will allow the normal timer frequency calculation to take place (based on the emulated RTC). Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Rewrite count/compare timer emulationJames Hogan2014-05-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously the emulation of the CPU timer was just enough to get a Linux guest running but some shortcuts were taken: - The guest timer interrupt was hard coded to always happen every 10 ms rather than being timed to when CP0_Count would match CP0_Compare. - The guest's CP0_Count register was based on the host's CP0_Count register. This isn't very portable and fails on cores without a CP_Count register implemented such as Ingenic XBurst. It also meant that the guest's CP0_Cause.DC bit to disable the CP0_Count register took no effect. - The guest's CP0_Count register was emulated by just dividing the host's CP0_Count register by 4. This resulted in continuity problems when used as a clock source, since when the host CP0_Count overflows from 0x7fffffff to 0x80000000, the guest CP0_Count transitions discontinuously from 0x1fffffff to 0xe0000000. Therefore rewrite & fix emulation of the guest timer based on the monotonic kernel time (i.e. ktime_get()). Internally a 32-bit count_bias value is added to the frequency scaled nanosecond monotonic time to get the guest's CP0_Count. The frequency of the timer is initialised to 100MHz and cannot yet be changed, but a later patch will allow the frequency to be configured via the KVM_{GET,SET}_ONE_REG ioctl interface. The timer can now be stopped via the CP0_Cause.DC bit (by the guest or via the KVM_SET_ONE_REG ioctl interface), at which point the current CP0_Count is stored and can be read directly. When it is restarted the bias is recalculated such that the CP0_Count value is continuous. Due to the nature of hrtimer interrupts any read of the guest's CP0_Count register while it is running triggers a check for whether the hrtimer has expired, so that the guest/userland cannot observe the CP0_Count passing CP0_Compare without queuing a timer interrupt. This is also taken advantage of when stopping the timer to ensure that a pending timer interrupt is queued. This replaces the implementation of: - Guest read of CP0_Count - Guest write of CP0_Count - Guest write of CP0_Compare - Guest write of CP0_Cause - Guest read of HWR 2 (CC) with RDHWR - Host read of CP0_Count via KVM_GET_ONE_REG ioctl interface - Host write of CP0_Count via KVM_SET_ONE_REG ioctl interface - Host write of CP0_Compare via KVM_SET_ONE_REG ioctl interface - Host write of CP0_Cause via KVM_SET_ONE_REG ioctl interface Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Migrate hrtimer to follow VCPUJames Hogan2014-05-30
| | | | | | | | | | | | | | | | | | When a VCPU is scheduled in on a different CPU, refresh the hrtimer used for emulating count/compare so that it gets migrated to the same CPU. This should prevent a timer interrupt occurring on a different CPU to where the guest it relates to is running, which would cause the guest timer interrupt not to be delivered until after the next guest exit. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Fix timer race modifying guest CP0_CauseJames Hogan2014-05-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The hrtimer callback for guest timer timeouts sets the guest's CP0_Cause.TI bit to indicate to the guest that a timer interrupt is pending, however there is no mutual exclusion implemented to prevent this occurring while the guest's CP0_Cause register is being read-modify-written elsewhere. When this occurs the setting of the CP0_Cause.TI bit is undone and the guest misses the timer interrupt and doesn't reprogram the CP0_Compare register for the next timeout. Currently another timer interrupt will be triggered again in another 10ms anyway due to the way timers are emulated, but after the MIPS timer emulation is fixed this would result in Linux guest time standing still and the guest scheduler not being invoked until the guest CP0_Count has looped around again, which at 100MHz takes just under 43 seconds. Currently this is the only asynchronous modification of guest registers, therefore it is fixed by adjusting the implementations of the kvm_set_c0_guest_cause(), kvm_clear_c0_guest_cause(), and kvm_change_c0_guest_cause() macros which are used for modifying the guest CP0_Cause register to use ll/sc to ensure atomic modification. This should work in both UP and SMP cases without requiring interrupts to be disabled. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Deliver guest interrupts after local_irq_disable()James Hogan2014-05-30
| | | | | | | | | | | | | | | | When about to run the guest, deliver guest interrupts after disabling host interrupts. This should prevent an hrtimer interrupt from being handled after delivering guest interrupts, and therefore not delivering the guest timer interrupt until after the next guest exit. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Add CP0_HWREna KVM register accessJames Hogan2014-05-30
| | | | | | | | | | | | | | | | Implement KVM_{GET,SET}_ONE_REG ioctl based access to the guest CP0 HWREna register. This is so that userland can save and restore its value so that RDHWR instructions don't have to be emulated by the guest. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: David Daney <david.daney@cavium.com> Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Add CP0_UserLocal KVM register accessJames Hogan2014-05-30
| | | | | | | | | | | | | | | | Implement KVM_{GET,SET}_ONE_REG ioctl based access to the guest CP0 UserLocal register. This is so that userland can save and restore its value. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: David Daney <david.daney@cavium.com> Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Add CP0_Count/Compare KVM register accessJames Hogan2014-05-30
| | | | | | | | | | | | | | | | | | | | | | | | Implement KVM_{GET,SET}_ONE_REG ioctl based access to the guest CP0 Count and Compare registers. These registers are special in that writing to them has side effects (adjusting the time until the next timer interrupt) and reading of Count depends on the time. Therefore add a couple of callbacks so that different implementations (trap & emulate or VZ) can implement them differently depending on what the hardware provides. The trap & emulate versions mostly duplicate what happens when a T&E guest reads or writes these registers, so it inherits the same limitations which can be fixed in later patches. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: David Daney <david.daney@cavium.com> Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Move KVM_{GET,SET}_ONE_REG definitions into kvm_host.hJames Hogan2014-05-30
| | | | | | | | | | | | | | | | | Move the KVM_{GET,SET}_ONE_REG MIPS register id definitions out of kvm_mips.c to kvm_host.h so that they can be shared between multiple source files. This allows register access to be indirected depending on the underlying implementation (trap & emulate or VZ). Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: David Daney <david.daney@cavium.com> Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Add CP0_EPC KVM register accessJames Hogan2014-05-30
| | | | | | | | | | | | | | | | Contrary to the comment, the guest CP0_EPC register cannot be set via kvm_regs, since it is distinct from the guest PC. Add the EPC register to the KVM_{GET,SET}_ONE_REG ioctl interface. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: David Daney <david.daney@cavium.com> Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Use tlb_write_randomJames Hogan2014-05-30
| | | | | | | | | | | | | | | | | | | | | | | When MIPS KVM needs to write a TLB entry for the guest it reads the CP0_Random register, uses it to generate the CP_Index, and writes the TLB entry using the TLBWI instruction (tlb_write_indexed()). However there's an instruction for that, TLBWR (tlb_write_random()) so use that instead. This happens to also fix an issue with Ingenic XBurst cores where the same TLB entry is replaced each time preventing forward progress on stores due to alternating between TLB load misses for the instruction fetch and TLB store misses. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Use local_flush_icache_range to fix RI on XBurstJames Hogan2014-05-30
| | | | | | | | | | | | | | | | | | | MIPS KVM uses mips32_SyncICache to synchronise the icache with the dcache after dynamically modifying guest instructions or writing guest exception vector. However this uses rdhwr to get the SYNCI step, which causes a reserved instruction exception on Ingenic XBurst cores. It would seem to make more sense to use local_flush_icache_range() instead which does the same thing but is more portable. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: Export local_flush_icache_range for KVMJames Hogan2014-05-30
| | | | | | | | | | | | | | | Export the local_flush_icache_range function pointer for GPL modules so that it can be used by KVM for syncing the icache after binary translation of trapping instructions. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* MIPS: KVM: Allocate at least 16KB for exception handlersJames Hogan2014-05-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Each MIPS KVM guest has its own copy of the KVM exception vector. This contains the TLB refill exception handler at offset 0x000, the general exception handler at offset 0x180, and interrupt exception handlers at offset 0x200 in case Cause_IV=1. A common handler is copied to offset 0x2000 and offset 0x3000 is used for temporarily storing k1 during entry from guest. However the amount of memory allocated for this purpose is calculated as 0x200 rounded up to the next page boundary, which is insufficient if 4KB pages are in use. This can lead to the common handler at offset 0x2000 being overwritten and infinitely recursive exceptions on the next exit from the guest. Increase the minimum size from 0x200 to 0x4000 to cover the full use of the page. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Merge tag 'kvm-s390-20140530' of ↵Paolo Bonzini2014-05-30
|\ | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kvm-next 1. Several minor fixes and cleanups for KVM: 2. Fix flag check for gdb support 3. Remove unnecessary vcpu start 4. Remove code duplication for sigp interrupts 5. Better DAT handling for the TPROT instruction 6. Correct addressing exception for standby memory
| * KVM: s390: Intercept the tprot instructionMatthew Rosato2014-05-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Based on original patch from Jeng-fang (Nick) Wang When standby memory is specified for a guest Linux, but no virtual memory has been allocated on the Qemu host backing that guest, the guest memory detection process encounters a memory access exception which is not thrown from the KVM handle_tprot() instruction-handler function. The access exception comes from sie64a returning EFAULT, which then passes an addressing exception to the guest. Unfortunately this does not the proper PSW fixup (nullifying vs. suppressing) so the guest will get a fault for the wrong address. Let's just intercept the tprot instruction all the time to do the right thing and not go the page fault handler path for standby memory. tprot is only used by Linux during startup so some exits should be ok. Without this patch, standby memory cannot be used with KVM. Signed-off-by: Nick Wang <jfwang@us.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Tested-by: Matthew Rosato <mjrosato@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * KVM: s390: a VCPU is already started when delivering interruptsDavid Hildenbrand2014-05-30
| | | | | | | | | | | | | | | | | | | | | | This patch removes the start of a VCPU when delivering a RESTART interrupt. Interrupt delivery is called from kvm_arch_vcpu_ioctl_run. So the VCPU is already considered started - no need to call kvm_s390_vcpu_start. This function will early exit anyway. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * KVM: s390: check the given debug flags, not the set onesDavid Hildenbrand2014-05-30
| | | | | | | | | | | | | | | | | | | | This patch fixes a minor bug when updating the guest debug settings. We should check the given debug flags, not the already set ones. Doesn't do any harm but too many (for now unused) flags could be set internally without error. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * KVM: s390: clean up interrupt injection in sigp codeJens Freimann2014-05-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have all the logic to inject interrupts available in kvm_s390_inject_vcpu(), so let's use it instead of injecting irqs manually to the list in sigp code. SIGP stop is special because we have to check the action_flags before injecting the interrupt. As the action_flags are not available in kvm_s390_inject_vcpu() we leave the code for the stop order code untouched for now. Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
| * KVM: s390: Enable DAT support for TPROT handlerThomas Huth2014-05-30
| | | | | | | | | | | | | | | | | | | | | | | | The TPROT instruction can be used to check the accessability of storage for any kind of logical addresses. So far, our handler only supported real addresses. This patch now also enables support for addresses that have to be translated via DAT first. And while we're at it, change the code to use the common KVM function gfn_to_hva_prot() to check for the validity and writability of the memory page. Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
| * KVM: s390: Add a generic function for translating guest addressesThomas Huth2014-05-30
| | | | | | | | | | | | | | | | This patch adds a function for translating logical guest addresses into physical guest addresses without touching the memory at the given location. Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
* | MIPS: KVM: remove the stale memory alias support function unalias_gfnDeng-Cheng Zhu2014-05-29
| | | | | | | | | | | | | | | | | | The memory alias support has been removed since a1f4d39500 (KVM: Remove memory alias support). So remove unalias_gfn from the MIPS port. Reviewed-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | arm: Fix compile warning for psciChristoffer Dall2014-05-27
| | | | | | | | | | | | | | | | | | | | | | | | Commit e71246a23acbc89e9cb4ebf1558d60e65733479f changes psci_init from a function returning a void to an int, but does not change the non CONFIG_ARM_PSCI implementation to return a value, which causes a compile warning. Just return 0. Cc: Ashwin Chaugule <ashwin.chaugule@linaro.org> Cc: Shawn Guo <shawn.guo@freescale.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | Merge tag 'kvm-arm-for-3.16' of ↵Paolo Bonzini2014-05-27
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-next Changed for the 3.16 merge window. This includes KVM support for PSCI v0.2 and also includes generic Linux support for PSCI v0.2 (on hosts that advertise that feature via their DT), since the latter depends on headers introduced by the former. Finally there's a small patch from Marc that enables Cortex-A53 support.
| * | arm64: KVM: Enable minimalistic support for Cortex-A53Marc Zyngier2014-05-25
| | | | | | | | | | | | | | | | | | | | | | | | In order to allow KVM to run on Cortex-A53 implementations, wire the minimal support required. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| * | ARM: Check if a CPU has gone offlineAshwin Chaugule2014-05-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PSCIv0.2 adds a new function called AFFINITY_INFO, which can be used to query if a specified CPU has actually gone offline. Calling this function via cpu_kill ensures that a CPU has quiesced after a call to cpu_die. This helps prevent the CPU from doing arbitrary bad things when data or instructions are clobbered (as happens with kexec) in the window between a CPU announcing that it is dead and said CPU leaving the kernel. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Rob Herring <robh@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
| * | PSCI: Add initial support for PSCIv0.2 functionsAshwin Chaugule2014-05-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The PSCIv0.2 spec defines standard values of function IDs and introduces a few new functions. Detect version of PSCI and appropriately select the right PSCI functions. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Reviewed-by: Rob Herring <robh@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
| * | ARM/ARM64: KVM: Advertise KVM_CAP_ARM_PSCI_0_2 to user spaceAnup Patel2014-04-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have PSCI v0.2 emulation available in KVM ARM/ARM64 hence advertise this to user space (i.e. QEMU or KVMTOOL) via KVM_CHECK_EXTENSION ioctl. Signed-off-by: Anup Patel <anup.patel@linaro.org> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| * | ARM/ARM64: KVM: Emulate PSCI v0.2 CPU_SUSPENDAnup Patel2014-04-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds emulation of PSCI v0.2 CPU_SUSPEND function call for KVM ARM/ARM64. This is a CPU-level function call which can suspend current CPU or current CPU cluster. We don't have VCPU clusters in KVM so we only suspend the current VCPU. The CPU_SUSPEND emulation is not tested much because currently there is no CPUIDLE driver in Linux kernel that uses PSCI CPU_SUSPEND. The PSCI CPU_SUSPEND implementation in ARM64 kernel was tested using a Simple CPUIDLE driver which is not published due to unstable DT-bindings for PSCI. (For more info, http://lwn.net/Articles/574950/) For simplicity, we implement CPU_SUSPEND emulation similar to WFI (Wait-for-interrupt) emulation and we also treat power-down request to be same as stand-by request. This is consistent with section 5.4.1 and section 5.4.2 of PSCI v0.2 specification. Signed-off-by: Anup Patel <anup.patel@linaro.org> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| * | ARM/ARM64: KVM: Fix CPU_ON emulation for PSCI v0.2Anup Patel2014-04-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As-per PSCI v0.2, the source CPU provides physical address of "entry point" and "context id" for starting a target CPU. Also, if target CPU is already running then we should return ALREADY_ON. Current emulation of CPU_ON function does not consider physical address of "context id" and returns INVALID_PARAMETERS if target CPU is already running. This patch updates kvm_psci_vcpu_on() such that it works for both PSCI v0.1 and PSCI v0.2. Signed-off-by: Anup Patel <anup.patel@linaro.org> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| * | ARM/ARM64: KVM: Emulate PSCI v0.2 MIGRATE_INFO_TYPE and related functionsAnup Patel2014-04-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds emulation of PSCI v0.2 MIGRATE, MIGRATE_INFO_TYPE, and MIGRATE_INFO_UP_CPU function calls for KVM ARM/ARM64. KVM ARM/ARM64 being a hypervisor (and not a Trusted OS), we cannot provide this functions hence we emulate these functions in following way: 1. MIGRATE - Returns "Not Supported" 2. MIGRATE_INFO_TYPE - Return 2 i.e. Trusted OS is not present 3. MIGRATE_INFO_UP_CPU - Returns "Not Supported" Signed-off-by: Anup Patel <anup.patel@linaro.org> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| * | ARM/ARM64: KVM: Emulate PSCI v0.2 AFFINITY_INFOAnup Patel2014-04-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds emulation of PSCI v0.2 AFFINITY_INFO function call for KVM ARM/ARM64. This is a VCPU-level function call which will be used to determine current state of given affinity level. Signed-off-by: Anup Patel <anup.patel@linaro.org> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| * | ARM/ARM64: KVM: Emulate PSCI v0.2 SYSTEM_OFF and SYSTEM_RESETAnup Patel2014-04-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The PSCI v0.2 SYSTEM_OFF and SYSTEM_RESET functions are system-level functions hence cannot be fully emulated by in-kernel PSCI emulation code. To tackle this, we forward PSCI v0.2 SYSTEM_OFF and SYSTEM_RESET function calls from vcpu to user space (i.e. QEMU or KVMTOOL) via kvm_run structure using KVM_EXIT_SYSTEM_EVENT exit reasons. Signed-off-by: Anup Patel <anup.patel@linaro.org> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| * | ARM/ARM64: KVM: Make kvm_psci_call() return convention more flexibleAnup Patel2014-04-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the kvm_psci_call() returns 'true' or 'false' based on whether the PSCI function call was handled successfully or not. This does not help us emulate system-level PSCI functions where the actual emulation work will be done by user space (QEMU or KVMTOOL). Examples of such system-level PSCI functions are: PSCI v0.2 SYSTEM_OFF and SYSTEM_RESET. This patch updates kvm_psci_call() to return three types of values: 1) > 0 (success) 2) = 0 (success but exit to user space) 3) < 0 (errors) Signed-off-by: Anup Patel <anup.patel@linaro.org> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| * | ARM/ARM64: KVM: Add base for PSCI v0.2 emulationAnup Patel2014-04-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the in-kernel PSCI emulation provides PSCI v0.1 interface to VCPUs. This patch extends current in-kernel PSCI emulation to provide PSCI v0.2 interface to VCPUs. By default, ARM/ARM64 KVM will always provide PSCI v0.1 interface for keeping the ABI backward-compatible. To select PSCI v0.2 interface for VCPUs, the user space (i.e. QEMU or KVMTOOL) will have to set KVM_ARM_VCPU_PSCI_0_2 feature when doing VCPU init using KVM_ARM_VCPU_INIT ioctl. Signed-off-by: Anup Patel <anup.patel@linaro.org> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
* | | KVM: x86: MOV CR/DR emulation should ignore modNadav Amit2014-05-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | MOV CR/DR instructions ignore the mod field (in the ModR/M byte). As the SDM states: "The 2 bits in the mod field are ignored". Accordingly, the second operand of these instructions is always a general purpose register. The current emulator implementation does not do so. If the mod bits do not equal 3, it expects the second operand to be in memory. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | | KVM: lapic: sync highest ISR to hardware apic on EOIPaolo Bonzini2014-05-27
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When Hyper-V enlightenments are in effect, Windows prefers to issue an Hyper-V MSR write to issue an EOI rather than an x2apic MSR write. The Hyper-V MSR write is not handled by the processor, and besides being slower, this also causes bugs with APIC virtualization. The reason is that on EOI the processor will modify the highest in-service interrupt (SVI) field of the VMCS, as explained in section 29.1.4 of the SDM; every other step in EOI virtualization is already done by apic_send_eoi or on VM entry, but this one is missing. We need to do the same, and be careful not to muck with the isr_count and highest_isr_cache fields that are unused when virtual interrupt delivery is enabled. Cc: stable@vger.kernel.org Reviewed-by: Yang Zhang <yang.z.zhang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: vmx: DR7 masking on task switch emulation is wrongNadav Amit2014-05-22
| | | | | | | | | | | | | | | | The DR7 masking which is done on task switch emulation should be in hex format (clearing the local breakpoints enable bits 0,2,4 and 6). Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | x86: fix page fault tracing when KVM guest support enabledDave Hansen2014-05-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I noticed on some of my systems that page fault tracing doesn't work: cd /sys/kernel/debug/tracing echo 1 > events/exceptions/enable cat trace; # nothing shows up I eventually traced it down to CONFIG_KVM_GUEST. At least in a KVM VM, enabling that option breaks page fault tracing, and disabling fixes it. I tried on some old kernels and this does not appear to be a regression: it never worked. There are two page-fault entry functions today. One when tracing is on and another when it is off. The KVM code calls do_page_fault() directly instead of calling the traced version: > dotraplinkage void __kprobes > do_async_page_fault(struct pt_regs *regs, unsigned long > error_code) > { > enum ctx_state prev_state; > > switch (kvm_read_and_reset_pf_reason()) { > default: > do_page_fault(regs, error_code); > break; > case KVM_PV_REASON_PAGE_NOT_PRESENT: I'm also having problems with the page fault tracing on bare metal (same symptom of no trace output). I'm unsure if it's related. Steven had an alternative to this which has zero overhead when tracing is off where this includes the standard noops even when tracing is disabled. I'm unconvinced that the extra complexity of his apporach: http://lkml.kernel.org/r/20140508194508.561ed220@gandalf.local.home is worth it, expecially considering that the KVM code is already making page fault entry slower here. This solution is dirt-simple. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org Cc: Peter Zijlstra <peterz@infradead.org> Cc: Gleb Natapov <gleb@redhat.com> Cc: kvm@vger.kernel.org Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: x86: get CPL from SS.DPLPaolo Bonzini2014-05-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CS.RPL is not equal to the CPL in the few instructions between setting CR0.PE and reloading CS. And CS.DPL is also not equal to the CPL for conforming code segments. However, SS.DPL *is* always equal to the CPL except for the weird case of SYSRET on AMD processors, which sets SS.DPL=SS.RPL from the value in the STAR MSR, but force CPL=3 (Intel instead forces SS.DPL=SS.RPL=CPL=3). So this patch: - modifies SVM to update the CPL from SS.DPL rather than CS.RPL; the above case with SYSRET is not broken further, and the way to fix it would be to pass the CPL to userspace and back - modifies VMX to always return the CPL from SS.DPL (except forcing it to 0 if we are emulating real mode via vm86 mode; in vm86 mode all DPLs have to be 3, but real mode does allow privileged instructions). It also removes the CPL cache, which becomes a duplicate of the SS access rights cache. This fixes doing KVM_IOCTL_SET_SREGS exactly after setting CR0.PE=1 but before CS has been reloaded. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: x86: check CS.DPL against RPL during task switchPaolo Bonzini2014-05-22
| | | | | | | | | | | | | | | | Table 7-1 of the SDM mentions a check that the code segment's DPL must match the selector's RPL. This was not done by KVM, fix it. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>