linux_dsm_epyc7002/arch/powerpc/kvm
Nicholas Piggin 082fa65bf6 KVM: PPC: Book3S HV P9: Restore host CTRL SPR after guest exit
[ Upstream commit 5088eb4092df12d701af8e0e92860b7186365279 ]

The host CTRL (runlatch) value is not restored after guest exit. The
host CTRL should always be 1 except in CPU idle code, so this can result
in the host running with runlatch clear, and potentially switching to
a different vCPU which then runs with runlatch clear as well.

This has little effect on P9 machines, CTRL is only responsible for some
PMU counter logic in the host and so other than corner cases of software
relying on that, or explicitly reading the runlatch value (Linux does
not appear to be affected but it's possible non-Linux guests could be),
there should be no execution correctness problem, though it could be
used as a covert channel between guests.

There may be microcontrollers, firmware or monitoring tools that sample
the runlatch value out-of-band, however since the register is writable
by guests, these values would (should) not be relied upon for correct
operation of the host, so suboptimal performance or incorrect reporting
should be the worst problem.

Fixes: 95a6432ce9 ("KVM: PPC: Book3S HV: Streamlined guest entry/exit path on P9 for radix guests")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210412014845.1517916-2-npiggin@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:35 +02:00
..
book3s_32_mmu_host.c KVM: PPC: Book3S PR: Move kvmppc_mmu_init() into PR KVM 2020-03-19 16:39:52 +11:00
book3s_32_mmu.c KVM: PPC: Use fallthrough; 2020-03-19 16:39:52 +11:00
book3s_32_sr.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 266 2019-06-05 17:30:28 +02:00
book3s_64_mmu_host.c KVM: PPC: Book3S PR: Move kvmppc_mmu_init() into PR KVM 2020-03-19 16:39:52 +11:00
book3s_64_mmu_hv.c KVM: PPC: Book3S HV: Increase KVMPPC_NR_LPIDS on POWER8 and POWER9 2020-07-21 15:38:03 +10:00
book3s_64_mmu_radix.c KVM: PPC: Book3S: Fix symbol undeclared warnings 2020-09-22 11:53:55 +10:00
book3s_64_mmu.c KVM: PPC: Use fallthrough; 2020-03-19 16:39:52 +11:00
book3s_64_slb.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 266 2019-06-05 17:30:28 +02:00
book3s_64_vio_hv.c treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
book3s_64_vio.c KVM: PPC: Book3S: Fix symbol undeclared warnings 2020-09-22 11:53:55 +10:00
book3s_emulate.c KVM: PPC: Clean up redundant 'kvm_run' parameters 2020-05-27 11:39:31 +10:00
book3s_exports.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 266 2019-06-05 17:30:28 +02:00
book3s_hv_builtin.c KVM: PPC: Book3S HV: simplify kvm_cma_reserve() 2020-10-13 18:38:34 -07:00
book3s_hv_hmi.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 114 2019-05-24 17:39:01 +02:00
book3s_hv_interrupts.S KVM: PPC: Book3S HV: Set LPCR[HDICE] before writing HDEC 2020-09-17 11:38:17 +10:00
book3s_hv_nested.c KVM: PPC: Book3S: Fix symbol undeclared warnings 2020-09-22 11:53:55 +10:00
book3s_hv_ras.c powerpc/64s: Move HMI IRQ stat from percpu variable to paca. 2020-07-29 23:47:53 +10:00
book3s_hv_rm_mmu.c powerpc: Define new SRR1 bits for a ISA v3.1 2020-05-19 00:10:38 +10:00
book3s_hv_rm_xics.c KVM: PPC: Book3S: Fix symbol undeclared warnings 2020-09-22 11:53:55 +10:00
book3s_hv_rm_xive.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
book3s_hv_rmhandlers.S powerpc/64s: handle ISA v3.1 local copy-paste context switches 2020-09-08 22:57:12 +10:00
book3s_hv_tm_builtin.c KVM: PPC: Book3S HV: Treat TM-related invalid form instructions on P9 like the valid ones 2020-03-19 16:39:52 +11:00
book3s_hv_tm.c KVM: PPC: Book3S HV: Treat TM-related invalid form instructions on P9 like the valid ones 2020-03-19 16:39:52 +11:00
book3s_hv_uvmem.c mm/memremap_pages: support multiple ranges per invocation 2020-10-13 18:38:28 -07:00
book3s_hv.c KVM: PPC: Book3S HV P9: Restore host CTRL SPR after guest exit 2021-05-14 09:50:35 +02:00
book3s_interrupts.S PPC KVM update for 5.9 2020-08-09 13:24:02 -04:00
book3s_mmu_hpte.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 266 2019-06-05 17:30:28 +02:00
book3s_paired_singles.c KVM: PPC: Clean up redundant 'kvm_run' parameters 2020-05-27 11:39:31 +10:00
book3s_pr_papr.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
book3s_pr.c KVM: PPC: Book3S: Fix symbol undeclared warnings 2020-09-22 11:53:55 +10:00
book3s_rmhandlers.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 266 2019-06-05 17:30:28 +02:00
book3s_rtas.c KVM: PPC: Protect kvm_vcpu_read_guest with srcu locks 2020-07-21 15:38:03 +10:00
book3s_segment.S powerpc/64s/exception: Move KVM test to common code 2020-04-01 13:42:11 +11:00
book3s_xics.c KVM: PPC: Book3S HV: XICS: Replace the 'destroy' method by a 'release' method 2020-09-03 14:12:48 +10:00
book3s_xics.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
book3s_xive_native.c KVM: PPC: Book3S HV: XIVE: Fix possible oops when accessing ESB page 2020-11-16 23:28:30 +11:00
book3s_xive_template.c powerpc/xive: Enforce load-after-store ordering when StoreEOI is active 2020-05-07 22:58:31 +10:00
book3s_xive.c KVM: PPC: Book3S HV: XIVE: Fix vCPU id sanity check 2020-12-01 21:45:51 +11:00
book3s_xive.h KVM: PPC: Book3S HV: XIVE: Make VP block size configurable 2019-10-22 16:29:02 +11:00
book3s.c KVM: PPC: Don't return -ENOTSUPP to userspace in ioctls 2020-09-17 11:38:17 +10:00
book3s.h KVM: PPC: Clean up redundant 'kvm_run' parameters 2020-05-27 11:39:31 +10:00
booke_emulate.c KVM: PPC: Clean up redundant 'kvm_run' parameters 2020-05-27 11:39:31 +10:00
booke_interrupts.S KVM: PPC: Clean up redundant kvm_run parameters in assembly 2020-07-23 15:50:01 +10:00
booke.c KVM: PPC: Don't return -ENOTSUPP to userspace in ioctls 2020-09-17 11:38:17 +10:00
booke.h KVM: PPC: Clean up redundant 'kvm_run' parameters 2020-05-27 11:39:31 +10:00
bookehv_interrupts.S KVM: PPC: Clean up redundant kvm_run parameters in assembly 2020-07-23 15:50:01 +10:00
e500_emulate.c KVM: PPC: Clean up redundant 'kvm_run' parameters 2020-05-27 11:39:31 +10:00
e500_mmu_host.c KVM: Pass MMU notifier range flags to kvm_unmap_hva_range() 2020-08-21 18:03:47 -04:00
e500_mmu_host.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
e500_mmu.c KVM: PPC: Kill kvmppc_ops::mmu_destroy() and kvmppc_mmu_destroy() 2020-03-19 16:43:07 +11:00
e500.c KVM: PPC: Kill kvmppc_ops::mmu_destroy() and kvmppc_mmu_destroy() 2020-03-19 16:43:07 +11:00
e500.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
e500mc.c KVM: PPC: Kill kvmppc_ops::mmu_destroy() and kvmppc_mmu_destroy() 2020-03-19 16:43:07 +11:00
emulate_loadstore.c MIPS: 2020-06-12 11:05:52 -07:00
emulate.c KVM: PPC: Clean up redundant 'kvm_run' parameters 2020-05-27 11:39:31 +10:00
fpu.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
irq.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile KVM: PPC: Book3S HV: Support for running secure guests 2019-11-28 16:30:02 +11:00
mpic.c KVM: Remove unnecessary asm/kvm_host.h includes 2020-03-16 17:57:34 +01:00
powerpc.c KVM: PPC: Make the VMX instruction emulation routines static 2021-03-04 11:38:01 +01:00
timing.c powerpc/kvm: no need to check return value of debugfs_create functions 2020-03-04 22:44:25 +11:00
timing.h KVM: Remove unnecessary asm/kvm_host.h includes 2020-03-16 17:57:34 +01:00
tm.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
trace_book3s.h KVM: PPC: Book3S: Simplify external interrupt handling 2018-10-09 16:04:27 +11:00
trace_booke.h KVM: PPC: Move and undef TRACE_INCLUDE_PATH/FILE 2018-11-07 23:04:38 +11:00
trace_hv.h KVM: PPC: Fix typo on H_DISABLE_AND_GET hcall 2020-07-23 17:43:35 +10:00
trace_pr.h KVM: PPC: Move and undef TRACE_INCLUDE_PATH/FILE 2018-11-07 23:04:38 +11:00
trace.h KVM: PPC: Move and undef TRACE_INCLUDE_PATH/FILE 2018-11-07 23:04:38 +11:00