Paul Mackerras e470571514 KVM: PPC: Book3S HV: Enable TM before accessing TM registers ... Commit 46a704f840 ("KVM: PPC: Book3S HV: Preserve userspace HTM state properly", 2017-06-15) added code to read transactional memory (TM) registers but forgot to enable TM before doing so. The result is that if userspace does have live values in the TM registers, a KVM_RUN ioctl will cause a host kernel crash like this: [ 181.328511] Unrecoverable TM Unavailable Exception f60 at d00000001e7d9980 [ 181.328605] Oops: Unrecoverable TM Unavailable Exception, sig: 6 [#1] [ 181.328613] SMP NR_CPUS=2048 [ 181.328613] NUMA [ 181.328618] PowerNV [ 181.328646] Modules linked in: vhost_net vhost tap nfs_layout_nfsv41_files rpcsec_gss_krb5 nfsv4 dns_resolver nfs +fscache 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 nf_reject_ipv4 tun ebtable_filter ebtables +ip6table_filter ip6_tables iptable_filter bridge stp llc kvm_hv kvm nfsd ses enclosure scsi_transport_sas ghash_generic +auth_rpcgss gf128mul xts sg ctr nfs_acl lockd vmx_crypto shpchp ipmi_powernv i2c_opal grace ipmi_devintf i2c_core +powernv_rng sunrpc ipmi_msghandler ibmpowernv uio_pdrv_genirq uio leds_powernv powernv_op_panel ip_tables xfs sd_mod +lpfc ipr bnx2x libata mdio ptp pps_core scsi_transport_fc libcrc32c dm_mirror dm_region_hash dm_log dm_mod [ 181.329278] CPU: 40 PID: 9926 Comm: CPU 0/KVM Not tainted 4.12.0+ #1 [ 181.329337] task: c000003fc6980000 task.stack: c000003fe4d80000 [ 181.329396] NIP: d00000001e7d9980 LR: d00000001e77381c CTR: d00000001e7d98f0 [ 181.329465] REGS: c000003fe4d837e0 TRAP: 0f60 Not tainted (4.12.0+) [ 181.329523] MSR: 9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE> [ 181.329527] CR: 24022448 XER: 00000000 [ 181.329608] CFAR: d00000001e773818 SOFTE: 1 [ 181.329608] GPR00: d00000001e77381c c000003fe4d83a60 d00000001e7ef410 c000003fdcfe0000 [ 181.329608] GPR04: c000003fe4f00000 0000000000000000 0000000000000000 c000003fd7954800 [ 181.329608] GPR08: 0000000000000001 c000003fc6980000 0000000000000000 d00000001e7e2880 [ 181.329608] GPR12: d00000001e7d98f0 c000000007b19000 00000001295220e0 00007fffc0ce2090 [ 181.329608] GPR16: 0000010011886608 00007fff8c89f260 0000000000000001 00007fff8c080028 [ 181.329608] GPR20: 0000000000000000 00000100118500a6 0000010011850000 0000010011850000 [ 181.329608] GPR24: 00007fffc0ce1b48 0000010011850000 00000000d673b901 0000000000000000 [ 181.329608] GPR28: 0000000000000000 c000003fdcfe0000 c000003fdcfe0000 c000003fe4f00000 [ 181.330199] NIP [d00000001e7d9980] kvmppc_vcpu_run_hv+0x90/0x6b0 [kvm_hv] [ 181.330264] LR [d00000001e77381c] kvmppc_vcpu_run+0x2c/0x40 [kvm] [ 181.330322] Call Trace: [ 181.330351] [c000003fe4d83a60] [d00000001e773478] kvmppc_set_one_reg+0x48/0x340 [kvm] (unreliable) [ 181.330437] [c000003fe4d83b30] [d00000001e77381c] kvmppc_vcpu_run+0x2c/0x40 [kvm] [ 181.330513] [c000003fe4d83b50] [d00000001e7700b4] kvm_arch_vcpu_ioctl_run+0x114/0x2a0 [kvm] [ 181.330586] [c000003fe4d83bd0] [d00000001e7642f8] kvm_vcpu_ioctl+0x598/0x7a0 [kvm] [ 181.330658] [c000003fe4d83d40] [c0000000003451b8] do_vfs_ioctl+0xc8/0x8b0 [ 181.330717] [c000003fe4d83de0] [c000000000345a64] SyS_ioctl+0xc4/0x120 [ 181.330776] [c000003fe4d83e30] [c00000000000b004] system_call+0x58/0x6c [ 181.330833] Instruction dump: [ 181.330869] e92d0260 e9290b50 e9290108 792807e3 41820058 e92d0260 e9290b50 e9290108 [ 181.330941] 792ae8a4 794a1f87 408204f4 e92d0260 <7d4022a6> f9490ff0 e92d0260 7d4122a6 [ 181.331013] ---[ end trace 6f6ddeb4bfe92a92 ]--- The fix is just to turn on the TM bit in the MSR before accessing the registers. Cc: stable@vger.kernel.org # v3.14+ Fixes: 46a704f840 ("KVM: PPC: Book3S HV: Preserve userspace HTM state properly") Reported-by: Jan Stancek <jstancek@redhat.com> Tested-by: Jan Stancek <jstancek@redhat.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>		2017-07-24 16:10:44 +10:00
..
alpha	tty: Fix TIOCGPTPEER ioctl definition	2017-07-17 17:04:41 +02:00
arc	arc: move generic-y of exported headers to uapi/asm/Kbuild	2017-07-10 03:43:21 +09:00
arm	Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2017-07-21 10:41:19 -07:00
arm64	Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2017-07-21 10:41:19 -07:00
blackfin	Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2017-07-21 10:41:19 -07:00
c6x	Merge branch 'work.uaccess-unaligned' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-07-15 11:17:52 -07:00
cris	Kbuild updates for v4.13 (2nd)	2017-07-13 13:37:57 -07:00
frv	FRV: tlbflush: move asmlinkage before return type	2017-07-12 16:26:04 -07:00
h8300	h8300: Add missing closing parenthesis in flat_get_addr_from_rp()	2017-07-16 09:24:06 -07:00
hexagon	hexagon: move generic-y of exported headers to uapi/asm/Kbuild	2017-07-10 03:43:26 +09:00
ia64	Merge branch 'work.uaccess-unaligned' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-07-15 11:17:52 -07:00
m32r	Merge branch 'work.uaccess-unaligned' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-07-15 11:17:52 -07:00
m68k	blackfin, m68k: Fix flat_set_persistent() for unsigned long to u32 changes	2017-07-16 09:24:06 -07:00
metag	metag: move generic-y of exported headers to uapi/asm/Kbuild	2017-07-10 03:43:30 +09:00
microblaze	Merge branch 'work.uaccess-unaligned' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-07-15 11:17:52 -07:00
mips	tty: Fix TIOCGPTPEER ioctl definition	2017-07-17 17:04:41 +02:00
mn10300	Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2017-07-21 10:41:19 -07:00
nios2	nios2: move generic-y of exported headers to uapi/asm/Kbuild	2017-07-11 21:33:43 +09:00
openrisc	openrisc: move generic-y of exported headers to uapi/asm/Kbuild	2017-07-11 21:33:50 +09:00
parisc	TTY/Serial fixes for 4.13-rc2	2017-07-22 09:00:24 -07:00
powerpc	KVM: PPC: Book3S HV: Enable TM before accessing TM registers	2017-07-24 16:10:44 +10:00
s390	Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2017-07-21 10:41:19 -07:00
score	Merge branch 'uaccess.strlen' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-07-06 22:07:44 -07:00
sh	TTY/Serial fixes for 4.13-rc2	2017-07-22 09:00:24 -07:00
sparc	TTY/Serial fixes for 4.13-rc2	2017-07-22 09:00:24 -07:00
tile	Merge branch 'work.uaccess-unaligned' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-07-15 11:17:52 -07:00
um	Merge branch 'for-linus-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml	2017-07-15 10:49:33 -07:00
unicore32	unicore32: move generic-y of exported headers to uapi/asm/Kbuild	2017-07-11 21:33:52 +09:00
x86	xen/x86: fix cpu hotplug	2017-07-23 08:13:11 +02:00
xtensa	tty: Fix TIOCGPTPEER ioctl definition	2017-07-17 17:04:41 +02:00
.gitignore
Kconfig	include/linux/string.h: add the option of fortified string.h functions	2017-07-12 16:26:03 -07:00