Commit Graph

518985 Commits

Author SHA1 Message Date
Paolo Bonzini
f36f3f2846 KVM: add "new" argument to kvm_arch_commit_memory_region
This lets the function access the new memory slot without going through
kvm_memslots and id_to_memslot.  It will simplify the code when more
than one address space will be supported.

Unfortunately, the "const"ness of the new argument must be casted
away in two places.  Fixing KVM to accept const struct kvm_memory_slot
pointers would require modifications in pretty much all architectures,
and is left for later.

Reviewed-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-28 10:42:58 +02:00
Paolo Bonzini
15f46015ee KVM: add memslots argument to kvm_arch_memslots_updated
Prepare for the case of multiple address spaces.

Reviewed-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-26 12:40:17 +02:00
Paolo Bonzini
09170a4942 KVM: const-ify uses of struct kvm_userspace_memory_region
Architecture-specific helpers are not supposed to muck with
struct kvm_userspace_memory_region contents.  Add const to
enforce this.

In order to eliminate the only write in __kvm_set_memory_region,
the cleaning of deleted slots is pulled up from update_memslots
to __kvm_set_memory_region.

Reviewed-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Reviewed-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-26 12:40:13 +02:00
Paolo Bonzini
9f6b802978 KVM: use kvm_memslots whenever possible
kvm_memslots provides lockdep checking.  Use it consistently instead of
explicit dereferencing of kvm->memslots.

Reviewed-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-26 12:40:08 +02:00
Paolo Bonzini
a47d2b07ea KVM: introduce kvm_alloc/free_memslots
kvm_alloc_memslots is extracted out of previously scattered code
that was in kvm_init_memslots_id and kvm_create_vm.

kvm_free_memslot and kvm_free_memslots are new names of
kvm_free_physmem and kvm_free_physmem_slot, but they also take
an explicit pointer to struct kvm_memslots.

This will simplify the transition to multiple address spaces,
each represented by one pointer to struct kvm_memslots.

Reviewed-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Reviewed-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-26 12:39:53 +02:00
Paolo Bonzini
a9b4fb7e79 Merge branch 'kvm-master' into kvm-next
Grab MPX bugfix, and fix conflicts against Rik's adaptive FPU
deactivation patch.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-20 12:31:37 +02:00
Liang Li
c447e76b4c kvm/fpu: Enable eager restore kvm FPU for MPX
The MPX feature requires eager KVM FPU restore support. We have verified
that MPX cannot work correctly with the current lazy KVM FPU restore
mechanism. Eager KVM FPU restore should be enabled if the MPX feature is
exposed to VM.

Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Signed-off-by: Liang Li <liang.z.li@intel.com>
[Also activate the FPU on AMD processors. - Paolo]
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-20 12:30:26 +02:00
Paolo Bonzini
0fdd74f778 Revert "KVM: x86: drop fpu_activate hook"
This reverts commit 4473b570a7.  We'll
use the hook again.

Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-20 12:30:15 +02:00
Andrea Arcangeli
e8fd5e9e99 kvm: fix crash in kvm_vcpu_reload_apic_access_page
memslot->userfault_addr is set by the kernel with a mmap executed
from the kernel but the userland can still munmap it and lead to the
below oops after memslot->userfault_addr points to a host virtual
address that has no vma or mapping.

[  327.538306] BUG: unable to handle kernel paging request at fffffffffffffffe
[  327.538407] IP: [<ffffffff811a7b55>] put_page+0x5/0x50
[  327.538474] PGD 1a01067 PUD 1a03067 PMD 0
[  327.538529] Oops: 0000 [#1] SMP
[  327.538574] Modules linked in: macvtap macvlan xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ipt_REJECT iptable_filter ip_tables tun bridge stp llc rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache xprtrdma ib_isert iscsi_target_mod ib_iser libiscsi scsi_transport_iscsi ib_srpt target_core_mod ib_srp scsi_transport_srp scsi_tgt ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm ipmi_devintf iTCO_wdt iTCO_vendor_support intel_powerclamp coretemp dcdbas intel_rapl kvm_intel kvm crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel lrw gf128mul glue_helper ablk_helper cryptd pcspkr sb_edac edac_core ipmi_si ipmi_msghandler acpi_pad wmi acpi_power_meter lpc_ich mfd_core mei_me
[  327.539488]  mei shpchp nfsd auth_rpcgss nfs_acl lockd grace sunrpc mlx4_ib ib_sa ib_mad ib_core mlx4_en vxlan ib_addr ip_tunnel xfs libcrc32c sd_mod crc_t10dif crct10dif_common crc32c_intel mgag200 syscopyarea sysfillrect sysimgblt i2c_algo_bit drm_kms_helper ttm drm ahci i2c_core libahci mlx4_core libata tg3 ptp pps_core megaraid_sas ntb dm_mirror dm_region_hash dm_log dm_mod
[  327.539956] CPU: 3 PID: 3161 Comm: qemu-kvm Not tainted 3.10.0-240.el7.userfault19.4ca4011.x86_64.debug #1
[  327.540045] Hardware name: Dell Inc. PowerEdge R420/0CN7CM, BIOS 2.1.2 01/20/2014
[  327.540115] task: ffff8803280ccf00 ti: ffff880317c58000 task.ti: ffff880317c58000
[  327.540184] RIP: 0010:[<ffffffff811a7b55>]  [<ffffffff811a7b55>] put_page+0x5/0x50
[  327.540261] RSP: 0018:ffff880317c5bcf8  EFLAGS: 00010246
[  327.540313] RAX: 00057ffffffff000 RBX: ffff880616a20000 RCX: 0000000000000000
[  327.540379] RDX: 0000000000002014 RSI: 00057ffffffff000 RDI: fffffffffffffffe
[  327.540445] RBP: ffff880317c5bd10 R08: 0000000000000103 R09: 0000000000000000
[  327.540511] R10: 0000000000000000 R11: 0000000000000000 R12: fffffffffffffffe
[  327.540576] R13: 0000000000000000 R14: ffff880317c5bd70 R15: ffff880317c5bd50
[  327.540643] FS:  00007fd230b7f700(0000) GS:ffff880630800000(0000) knlGS:0000000000000000
[  327.540717] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  327.540771] CR2: fffffffffffffffe CR3: 000000062a2c3000 CR4: 00000000000427e0
[  327.540837] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  327.540904] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  327.540974] Stack:
[  327.541008]  ffffffffa05d6d0c ffff880616a20000 0000000000000000 ffff880317c5bdc0
[  327.541093]  ffffffffa05ddaa2 0000000000000000 00000000002191bf 00000042f3feab2d
[  327.541177]  00000042f3feab2d 0000000000000002 0000000000000001 0321000000000000
[  327.541261] Call Trace:
[  327.541321]  [<ffffffffa05d6d0c>] ? kvm_vcpu_reload_apic_access_page+0x6c/0x80 [kvm]
[  327.543615]  [<ffffffffa05ddaa2>] vcpu_enter_guest+0x3f2/0x10f0 [kvm]
[  327.545918]  [<ffffffffa05e2f10>] kvm_arch_vcpu_ioctl_run+0x2b0/0x5a0 [kvm]
[  327.548211]  [<ffffffffa05e2d02>] ? kvm_arch_vcpu_ioctl_run+0xa2/0x5a0 [kvm]
[  327.550500]  [<ffffffffa05ca845>] kvm_vcpu_ioctl+0x2b5/0x680 [kvm]
[  327.552768]  [<ffffffff810b8d12>] ? creds_are_invalid.part.1+0x12/0x50
[  327.555069]  [<ffffffff810b8d71>] ? creds_are_invalid+0x21/0x30
[  327.557373]  [<ffffffff812d6066>] ? inode_has_perm.isra.49.constprop.65+0x26/0x80
[  327.559663]  [<ffffffff8122d985>] do_vfs_ioctl+0x305/0x530
[  327.561917]  [<ffffffff8122dc51>] SyS_ioctl+0xa1/0xc0
[  327.564185]  [<ffffffff816de829>] system_call_fastpath+0x16/0x1b
[  327.566480] Code: 0b 31 f6 4c 89 e7 e8 4b 7f ff ff 0f 0b e8 24 fd ff ff e9 a9 fd ff ff 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 <48> f7 07 00 c0 00 00 55 48 89 e5 75 2a 8b 47 1c 85 c0 74 1e f0

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-20 12:30:06 +02:00
Nicholas Krause
ed3cf15271 kvm: x86: Make functions that have no external callers static
This makes the functions kvm_guest_cpu_init and  kvm_init_debugfs
static now due to having no external callers outside their
declarations in the file, kvm.c.

Signed-off-by: Nicholas Krause <xerofoify@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-20 11:48:21 +02:00
Paolo Bonzini
3520469d65 KVM: export __gfn_to_pfn_memslot, drop gfn_to_pfn_async
gfn_to_pfn_async is used in just one place, and because of x86-specific
treatment that place will need to look at the memory slot.  Hence inline
it into try_async_pf and export __gfn_to_pfn_memslot.

The patch also switches the subsequent call to gfn_to_pfn_prot to use
__gfn_to_pfn_memslot.  This is a small optimization.  Finally, remove
the now-unused async argument of __gfn_to_pfn.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:45 +02:00
Paolo Bonzini
69a1220060 KVM: mips: use id_to_memslot correctly
The argument to KVM_GET_DIRTY_LOG is a memslot id; it may not match the
position in the memslots array, which is sorted by gfn.

Cc: stable@vger.kernel.org
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:44 +02:00
Xiao Guangrong
d81135a57a KVM: x86: do not reset mmu if CR0.CD and CR0.NW are changed
CR0.CD and CR0.NW are not used by shadow page table so that need
not adjust mmu if these two bit are changed

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:43 +02:00
Xiao Guangrong
efdfe536d8 KVM: MMU: fix MTRR update
Currently, whenever guest MTRR registers are changed
kvm_mmu_reset_context is called to switch to the new root shadow page
table, however, it's useless since:
1) the cache type is not cached into shadow page's attribute so that
   the original root shadow page will be reused

2) the cache type is set on the last spte, that means we should sync
   the last sptes when MTRR is changed

This patch fixs this issue by drop all the spte in the gfn range which
is being updated by MTRR

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:42 +02:00
Xiao Guangrong
d69afbc6b1 KVM: MMU: fix decoding cache type from MTRR
There are some bugs in current get_mtrr_type();
1: bit 1 of mtrr_state->enabled is corresponding bit 11 of
   IA32_MTRR_DEF_TYPE MSR which completely control MTRR's enablement
   that means other bits are ignored if it is cleared

2: the fixed MTRR ranges are controlled by bit 0 of
   mtrr_state->enabled (bit 10 of IA32_MTRR_DEF_TYPE)

3: if MTRR is disabled, UC is applied to all of physical memory rather
   than mtrr_state->def_type

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Reviewed-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:42 +02:00
Xiao Guangrong
6a49f85c7a KVM: MMU: introduce kvm_zap_rmapp
Split kvm_unmap_rmapp and introduce kvm_zap_rmapp which will be used in the
later patch

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:41 +02:00
Xiao Guangrong
d77aa73c70 KVM: MMU: use slot_handle_level and its helper to clean up the code
slot_handle_level and its helper functions are ready now, use them to
clean up the code

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:41 +02:00
Xiao Guangrong
1bad2b2a3b KVM: MMU: introduce slot_handle_level_range() and its helpers
There are several places walking all rmaps for the memslot so that
introduce common functions to cleanup the code

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:40 +02:00
Xiao Guangrong
6ce1f4e295 KVM: MMU: introduce for_each_slot_rmap_range
It's used to abstract the code from kvm_handle_hva_range and it will be
used by later patch

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:39 +02:00
Xiao Guangrong
8a3d08f16f KVM: MMU: introduce PT_MAX_HUGEPAGE_LEVEL
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:39 +02:00
Xiao Guangrong
0d5367900a KVM: MMU: introduce for_each_rmap_spte()
It's used to walk all the sptes on the rmap to clean up the
code

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:38 +02:00
Paolo Bonzini
c35ebbeade Revert "kvmclock: set scheduler clock stable"
This reverts commit ff7bbb9c6a.
Sasha Levin is seeing odd jump in time values during boot of a KVM guest:

[...]
[    0.000000] tsc: Detected 2260.998 MHz processor
[3376355.247558] Calibrating delay loop (skipped) preset value..
[...]

and bisected them to this commit.

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:37 +02:00
Xiao Guangrong
edc90b7dc4 KVM: MMU: fix SMAP virtualization
KVM may turn a user page to a kernel page when kernel writes a readonly
user page if CR0.WP = 1. This shadow page entry will be reused after
SMAP is enabled so that kernel is allowed to access this user page

Fix it by setting SMAP && !CR0.WP into shadow page's role and reset mmu
once CR4.SMAP is updated

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:36 +02:00
Nadav Amit
428e3d0857 KVM: x86: Fix zero iterations REP-string
When a REP-string is executed in 64-bit mode with an address-size prefix,
ECX/EDI/ESI are used as counter and pointers. When ECX is initially zero, Intel
CPUs clear the high 32-bits of RCX, and recent Intel CPUs update the high bits
of the pointers in MOVS/STOS. This behavior is specific to Intel according to
few experiments.

As one may guess, this is an undocumented behavior. Yet, it is observable in
the guest, since at least VMX traps REP-INS/OUTS even when ECX=0. Note that
VMware appears to get it right.  The behavior can be observed using the
following code:

 #include <stdio.h>

 #define LOW_MASK	(0xffffffff00000000ull)
 #define ALL_MASK	(0xffffffffffffffffull)
 #define TEST(opcode)							\
	do {								\
	asm volatile(".byte 0xf2 \n\t .byte 0x67 \n\t .byte " opcode "\n\t" \
			: "=S"(s), "=c"(c), "=D"(d) 			\
			: "S"(ALL_MASK), "c"(LOW_MASK), "D"(ALL_MASK));	\
	printf("opcode %s rcx=%llx rsi=%llx rdi=%llx\n",		\
		opcode, c, s, d);					\
	} while(0)

void main()
{
	unsigned long long s, d, c;
	iopl(3);
	TEST("0x6c");
	TEST("0x6d");
	TEST("0x6e");
	TEST("0x6f");
	TEST("0xa4");
	TEST("0xa5");
	TEST("0xa6");
	TEST("0xa7");
	TEST("0xaa");
	TEST("0xab");
	TEST("0xae");
	TEST("0xaf");
}

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:36 +02:00
Nadav Amit
ee122a7109 KVM: x86: Fix update RCX/RDI/RSI on REP-string
When REP-string instruction is preceded with an address-size prefix,
ECX/EDI/ESI are used as the operation counter and pointers.  When they are
updated, the high 32-bits of RCX/RDI/RSI are cleared, similarly to the way they
are updated on every 32-bit register operation.  Fix it.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:35 +02:00
Nadav Amit
3db176d5b4 KVM: x86: Fix DR7 mask on task-switch while debugging
If the host sets hardware breakpoints to debug the guest, and a task-switch
occurs in the guest, the architectural DR7 will not be updated. The effective
DR7 would be updated instead.

This fix puts the DR7 update during task-switch emulation, so it now uses the
standard DR setting mechanism instead of the one that was previously used. As a
bonus, the update of DR7 will now be effective for AMD as well.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-19 20:52:35 +02:00
Xiao Guangrong
0be0226f07 KVM: MMU: fix SMAP virtualization
KVM may turn a user page to a kernel page when kernel writes a readonly
user page if CR0.WP = 1. This shadow page entry will be reused after
SMAP is enabled so that kernel is allowed to access this user page

Fix it by setting SMAP && !CR0.WP into shadow page's role and reset mmu
once CR4.SMAP is updated

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-11 17:17:50 +02:00
Paolo Bonzini
898761158b KVM: MMU: fix CR4.SMEP=1, CR0.WP=0 with shadow pages
smep_andnot_wp is initialized in kvm_init_shadow_mmu and shadow pages
should not be reused for different values of it.  Thus, it has to be
added to the mask in kvm_mmu_pte_write.

Reviewed-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-11 17:17:44 +02:00
Xiao Guangrong
7cbeed9bce KVM: MMU: fix smap permission check
Current permission check assumes that RSVD bit in PFEC is always zero,
however, it is not true since MMIO #PF will use it to quickly identify
MMIO access

Fix it by clearing the bit if walking guest page table is needed

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-11 17:17:23 +02:00
Paolo Bonzini
cba3d2765e KVM: s390: Fixes and features for 4.2 (kvm/next)
Mostly a bunch of fixes, reworks and optimizations for s390.
 There is one new feature (EDAT-2 inside the guest), which boils
 down to 2GB pages.
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Merge tag 'kvm-s390-next-20150508' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: Fixes and features for 4.2 (kvm/next)

Mostly a bunch of fixes, reworks and optimizations for s390.
There is one new feature (EDAT-2 inside the guest), which boils
down to 2GB pages.
2015-05-11 14:06:32 +02:00
Paul Mackerras
17d489019c KVM: PPC: Book3S HV: Fix list traversal in error case
This fixes a regression introduced in commit 25fedfca94, "KVM: PPC:
Book3S HV: Move vcore preemption point up into kvmppc_run_vcpu", which
leads to a user-triggerable oops.

In the case where we try to run a vcore on a physical core that is
not in single-threaded mode, or the vcore has too many threads for
the physical core, we iterate the list of runnable vcpus to make
each one return an EBUSY error to userspace.  Since this involves
taking each vcpu off the runnable_threads list for the vcore, we
need to use list_for_each_entry_safe rather than list_for_each_entry
to traverse the list.  Otherwise the kernel will crash with an oops
message like this:

Unable to handle kernel paging request for data at address 0x000fff88
Faulting instruction address: 0xd00000001e635dc8
Oops: Kernel access of bad area, sig: 11 [#2]
SMP NR_CPUS=1024 NUMA PowerNV
...
CPU: 48 PID: 91256 Comm: qemu-system-ppc Tainted: G      D        3.18.0 #1
task: c00000274e507500 ti: c0000027d1924000 task.ti: c0000027d1924000
NIP: d00000001e635dc8 LR: d00000001e635df8 CTR: c00000000011ba50
REGS: c0000027d19275b0 TRAP: 0300   Tainted: G      D         (3.18.0)
MSR: 9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE>  CR: 22002824  XER: 00000000
CFAR: c000000000008468 DAR: 00000000000fff88 DSISR: 40000000 SOFTE: 1
GPR00: d00000001e635df8 c0000027d1927830 d00000001e64c850 0000000000000001
GPR04: 0000000000000001 0000000000000001 0000000000000000 0000000000000000
GPR08: 0000000000200200 0000000000000000 0000000000000000 d00000001e63e588
GPR12: 0000000000002200 c000000007dbc800 c000000fc7800000 000000000000000a
GPR16: fffffffffffffffc c000000fd5439690 c000000fc7801c98 0000000000000001
GPR20: 0000000000000003 c0000027d1927aa8 c000000fd543b348 c000000fd543b350
GPR24: 0000000000000000 c000000fa57f0000 0000000000000030 0000000000000000
GPR28: fffffffffffffff0 c000000fd543b328 00000000000fe468 c000000fd543b300
NIP [d00000001e635dc8] kvmppc_run_core+0x198/0x17c0 [kvm_hv]
LR [d00000001e635df8] kvmppc_run_core+0x1c8/0x17c0 [kvm_hv]
Call Trace:
[c0000027d1927830] [d00000001e635df8] kvmppc_run_core+0x1c8/0x17c0 [kvm_hv] (unreliable)
[c0000027d1927a30] [d00000001e638350] kvmppc_vcpu_run_hv+0x5b0/0xdd0 [kvm_hv]
[c0000027d1927b70] [d00000001e510504] kvmppc_vcpu_run+0x44/0x60 [kvm]
[c0000027d1927ba0] [d00000001e50d4a4] kvm_arch_vcpu_ioctl_run+0x64/0x170 [kvm]
[c0000027d1927be0] [d00000001e504be8] kvm_vcpu_ioctl+0x5e8/0x7a0 [kvm]
[c0000027d1927d40] [c0000000002d6720] do_vfs_ioctl+0x490/0x780
[c0000027d1927de0] [c0000000002d6ae4] SyS_ioctl+0xd4/0xf0
[c0000027d1927e30] [c000000000009358] syscall_exit+0x0/0x98
Instruction dump:
60000000 60420000 387e1b30 38800003 38a00001 38c00000 480087d9 e8410018
ebde1c98 7fbdf040 3bdee368 419e0048 <813e1b20> 939e1b18 2f890001 409effcc
---[ end trace 8cdf50251cca6680 ]---

Fixes: 25fedfca94
Signed-off-by: Paul Mackerras <paulus@samba.org>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-10 17:26:05 +02:00
David Hildenbrand
06b36753a6 KVM: s390: drop handling of interception code 12
Our implementation will never trigger interception code 12 as the
responsible setting is never enabled - and never will be.
The handler is dead code. Let's get rid of it.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-05-08 15:51:17 +02:00
David Hildenbrand
96e0ed23dc KVM: s390: factor out and optimize floating irq VCPU kick
This patch factors out the search for a floating irq destination
VCPU as well as the kicking of the found VCPU. The search is optimized
in the following ways:

1. stopped VCPUs can't take any floating interrupts, so try to find an
   operating one. We have to take care of the special case where all
   VCPUs are stopped and we don't have any valid destination.

2. use online_vcpus, not KVM_MAX_VCPU. This speeds up the search
   especially if KVM_MAX_VCPU is increased one day. As these VCPU
   objects are initialized prior to increasing online_vcpus, we can be
   sure that they exist.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Reviewed-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-05-08 15:51:16 +02:00
Jens Freimann
ffeca0ae88 KVM: s390: optimize interrupt handling round trip time
We can avoid checking guest control registers and guest PSW as well
as all the masking and calculations on the interrupt masks when
no interrupts are pending.

Also, the check for IRQ_PEND_COUNT can be removed, because we won't
enter the while loop if no interrupts are pending and invalid interrupt
types can't be injected.

Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-05-08 15:51:15 +02:00
Christian Borntraeger
27406cd50c KVM: s390: provide functions for blocking all CPUs
Some updates to the control blocks need to be done in a way that
ensures that no CPU is within SIE. Provide wrappers around the
s390_vcpu_block functions and adopt the TOD migration code to
update in a guaranteed fashion. Also rename these functions to
have the kvm_s390_ prefix as everything else.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
2015-05-08 15:51:15 +02:00
Christian Borntraeger
8e23654687 KVM: s390: make exit_sie_sync more robust
exit_sie_sync is used to kick CPUs out of SIE and prevent reentering at
any point in time. This is used to reload the prefix pages and to
set the IBS stuff in a way that guarantees that after this function
returns we are no longer in SIE. All current users trigger KVM requests.

The request must be set before we block the CPUs to avoid races. Let's
make this implicit by adding the request into a new function
kvm_s390_sync_requests that replaces exit_sie_sync and split out
s390_vcpu_block and s390_vcpu_unblock, that can be used to keep
CPUs out of SIE independent of requests.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-05-08 15:51:14 +02:00
Guenther Hutzl
53df84f8de KVM: s390: Enable guest EDAT2 support
1. Enable EDAT2 in the list of KVM facilities

2. Handle 2G frames in pfmf instruction
If we support EDAT2, we may enable handling of 2G frames if not in 24
bit mode.

3. Enable EDAT2 in sie_block
If the EDAT2 facility is available we enable GED2 mode control in the
sie_block.

Reviewed-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>
Signed-off-by: Guenther Hutzl <hutzl@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-05-08 15:51:14 +02:00
Guenther Hutzl
a4a4f1916a KVM: s390: make EDAT1 depend on host support
We should only enable EDAT1 for the guest if the host actually supports
it and the cpu model for the guest has EDAT-1 enabled.

Reviewed-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>
Signed-off-by: Guenther Hutzl <hutzl@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-05-08 15:51:13 +02:00
Christian Borntraeger
785dbef407 KVM: s390: optimize round trip time in request handling
The fast path for a sie exit is that no kvm reqest is pending.
Make an early check to skip all single bit checks.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-05-08 15:51:12 +02:00
David Hildenbrand
b938eacea0 KVM: s390: fix external call injection without sigp interpretation
Commit ea5f496925 ("KVM: s390: only one external call may be pending
at a time") introduced a bug on machines that don't have SIGP
interpretation facility installed.
The injection of an external call will now always fail with -EBUSY
(if none is already pending).

This leads to the following symptoms:
- An external call will be injected but with the wrong "src cpu id",
  as this id will not be remembered.
- The target vcpu will not be woken up, therefore the guest will hang if
  it cannot deal with unexpected failures of the SIGP EXTERNAL CALL
  instruction.
- If an external call is already pending, -EBUSY will not be reported.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # v4.0
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-05-08 15:51:12 +02:00
Paolo Bonzini
31fd9880a1 KVM: MMU: fix CR4.SMEP=1, CR0.WP=0 with shadow pages
smep_andnot_wp is initialized in kvm_init_shadow_mmu and shadow pages
should not be reused for different values of it.  Thus, it has to be
added to the mask in kvm_mmu_pte_write.

Reviewed-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-08 10:51:47 +02:00
Xiao Guangrong
ceee7df749 KVM: MMU: fix smap permission check
Current permission check assumes that RSVD bit in PFEC is always zero,
however, it is not true since MMIO #PF will use it to quickly identify
MMIO access

Fix it by clearing the bit if walking guest page table is needed

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-08 10:51:47 +02:00
Heiko Carstens
a4cca3b419 KVM: remove pointless cpu hotplug messages
On cpu hotplug only KVM emits an unconditional message that its notifier
has been called. It certainly can be assumed that calling cpu hotplug
notifiers work, therefore there is no added value if KVM prints a message.

If an error happens on cpu online KVM will still emit a warning.

So let's remove this superfluous message.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-08 10:51:46 +02:00
Jan Kiszka
8a9781f7ad KVM: nVMX: Fix host crash when loading MSRs with userspace irqchip
vcpu->arch.apic is NULL when a userspace irqchip is active. But instead
of letting the test incorrectly depend on in-kernel irqchip mode,
open-code it to catch also userspace x2APICs.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-08 10:51:45 +02:00
Nadav Amit
acac6f8957 KVM: x86: Call-far should not be emulated as stack op
Far call in 64-bit has a 32-bit operand size. Remove the marking of this
operation as Stack so it can be emulated correctly in 64-bit.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-08 10:51:44 +02:00
Radim Krčmář
251eb84144 KVM: reuse memslot in kvm_write_guest_page
Caching memslot value and using mark_page_dirty_in_slot() avoids another
O(log N) search when dirtying the page.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Message-Id: <1428695247-27603-1-git-send-email-rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-08 10:51:38 +02:00
Paolo Bonzini
4eb64dce8d KVM: x86: dump VMCS on invalid entry
Code and format roughly based on Xen's vmcs_dump_vcpu.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-07 11:30:40 +02:00
Marcelo Tosatti
a3eb97bd80 x86: kvmclock: drop rdtsc_barrier()
Drop unnecessary rdtsc_barrier(), as has been determined empirically,
see 057e6a8c66 for details.

Noticed by Andy Lutomirski.

Improves clock_gettime() by approximately 15% on
Intel i7-3520M @ 2.90GHz.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-07 11:29:48 +02:00
Julia Lawall
d90e3a35e9 KVM: x86: drop unneeded null test
If the null test is needed, the call to cancel_delayed_work_sync would have
already crashed.  Normally, the destroy function should only be called
if the init function has succeeded, in which case ioapic is not null.

Problem found using Coccinelle.

Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-07 11:29:47 +02:00
Radim Krčmář
74545705cb KVM: x86: fix initial PAT value
PAT should be 0007_0406_0007_0406h on RESET and not modified on INIT.
VMX used a wrong value (host's PAT) and while SVM used the right one,
it never got to arch.pat.

This is not an issue with QEMU as it will force the correct value.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-07 11:29:46 +02:00