Instead of taking a pointer to struct user_ctxs like the other two
restore_blah_context() functions the FPSIMD function takes a pointer to the
user struct it should read. Change it to be consistent with the rest, both
for consistency and to prepare for changes which avoid rereading data that
has already been read by the core parsing code.
There should be no functional change from this patch.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-3-4545c94b20ff@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
There is some minimal size validation in parse_user_sigframe() however
all of the individual parsing functions perform frame specific validation
of the sizing information, remove the frame specific size checks in the
core so that there isn't any confusion about what we validate for size.
Since the checks in the SVE and ZA parsing are after we have read the
relevant context and since they won't report an error if the frame is
undersized they are adjusted to check for this before doing anything else.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-2-4545c94b20ff@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Implement support for a new note type NT_ARM64_ZT providing access to
ZT0 when implemented. Since ZT0 is a register with constant size this is
much simpler than for other SME state.
As ZT0 is only accessible when PSTATE.ZA is set writes to ZT0 cause
PSTATE.ZA to be set, the main alternative would be to return -EBUSY in
this case but this seemed more constructive. Practical users are also
going to be working with ZA anyway and have some understanding of the
state.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221208-arm64-sme2-v4-12-f2fa0aef982f@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add a new signal context type for ZT which is present in the signal frame
when ZA is enabled and ZT is supported by the system. In order to account
for the possible addition of further ZT registers in the future we make the
number of registers variable in the ABI, though currently the only possible
number is 1. We could just use a bare list head for the context since the
number of registers can be inferred from the size of the context but for
usability and future extensibility we define a header with the number of
registers and some reserved fields in it.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221208-arm64-sme2-v4-11-f2fa0aef982f@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
When the system supports SME2 there is an additional register ZT0 which
we must store when the task is using SME. Since ZT0 is accessible only
when PSTATE.ZA is set just like ZA we allocate storage for it along with
ZA, increasing the allocation size for the memory region where we store
ZA and storing the data for ZT after that for ZA.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221208-arm64-sme2-v4-9-f2fa0aef982f@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
In preparation for adding support for storage for ZT0 to the thread_struct
rename za_state to sme_state. Since ZT0 is accessible when PSTATE.ZA is
set just like ZA itself we will extend the allocation done for ZA to
cover it, avoiding the need to further expand task_struct for non-SME
tasks.
No functional changes.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221208-arm64-sme2-v4-1-f2fa0aef982f@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Pull powerpc fixes from Michael Ellerman:
- Three fixes for various bogosity in our linker script, revealed
by the recent commit which changed discard behaviour with some
toolchains.
* tag 'powerpc-6.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/vmlinux.lds: Don't discard .comment
powerpc/vmlinux.lds: Don't discard .rela* for relocatable builds
powerpc/vmlinux.lds: Define RUNTIME_DISCARD_EXIT
Pull devicetree fixes from Rob Herring:
- Fix DT memory scanning for some MIPS boards when memory is not
specified in DT
- Redo CONFIG_CMDLINE* handling for missing /chosen node. The first
attempt broke PS3 (and possibly other PPC platforms).
- Fix constraints in QCom Soundwire schema
* tag 'devicetree-fixes-for-6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
of: fdt: Honor CONFIG_CMDLINE* even without /chosen node, take 2
Revert "of: fdt: Honor CONFIG_CMDLINE* even without /chosen node"
dt-bindings: soundwire: qcom,soundwire: correct sizes related to number of ports
of/fdt: run soc memory setup when early_init_dt_scan_memory fails
Pull arm TIF_NOTIFY_SIGNAL fixup from Jens Axboe:
"Hui Tang reported a performance regressions with _TIF_WORK_MASK in
newer kernels, which he tracked to a change that went into 5.11. After
this change, we'll call do_work_pending() more often than we need to,
because we're now testing bits 0..15 rather than just 0..7.
Shuffle the bits around to avoid this"
* tag 'tif-notify-signal-2023-01-06' of git://git.kernel.dk/linux:
ARM: renumber bits related to _TIF_WORK_MASK
Pull RISC-V fixes from Palmer Dabbelt:
- use the correct mask for c.jr/c.jalr when decoding instructions
- build fix for get_user() to avoid a sparse warning
* tag 'riscv-for-linus-6.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: uaccess: fix type of 0 variable on error in get_user()
riscv, kprobes: Stricter c.jr/c.jalr decoding
Pull perf fix from Ingo Molnar:
"Intel RAPL updates for new model IDs"
* tag 'perf-urgent-2023-01-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/rapl: Add support for Intel Emerald Rapids
perf/x86/rapl: Add support for Intel Meteor Lake
perf/x86/rapl: Treat Tigerlake like Icelake
Pull crypto fixes from Herbert Xu:
"This fixes a CFI crash in arm64/sm4 as well as a regression in the
caam driver"
* tag 'v6.2-p2' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: arm64/sm4 - fix possible crash with CFI enabled
crypto: caam - fix CAAM io mem access in blob_gen
Pull networking fixes from Jakub Kicinski:
"Including fixes from bpf, wifi, and netfilter.
Current release - regressions:
- bpf: fix nullness propagation for reg to reg comparisons, avoid
null-deref
- inet: control sockets should not use current thread task_frag
- bpf: always use maximal size for copy_array()
- eth: bnxt_en: don't link netdev to a devlink port for VFs
Current release - new code bugs:
- rxrpc: fix a couple of potential use-after-frees
- netfilter: conntrack: fix IPv6 exthdr error check
- wifi: iwlwifi: fw: skip PPAG for JF, avoid FW crashes
- eth: dsa: qca8k: various fixes for the in-band register access
- eth: nfp: fix schedule in atomic context when sync mc address
- eth: renesas: rswitch: fix getting mac address from device tree
- mobile: ipa: use proper endpoint mask for suspend
Previous releases - regressions:
- tcp: add TIME_WAIT sockets in bhash2, fix regression caught by
Jiri / python tests
- net: tc: don't intepret cls results when asked to drop, fix
oob-access
- vrf: determine the dst using the original ifindex for multicast
- eth: bnxt_en:
- fix XDP RX path if BPF adjusted packet length
- fix HDS (header placement) and jumbo thresholds for RX packets
- eth: ice: xsk: do not use xdp_return_frame() on tx_buf->raw_buf,
avoid memory corruptions
Previous releases - always broken:
- ulp: prevent ULP without clone op from entering the LISTEN status
- veth: fix race with AF_XDP exposing old or uninitialized
descriptors
- bpf:
- pull before calling skb_postpull_rcsum() (fix checksum support
and avoid a WARN())
- fix panic due to wrong pageattr of im->image (when livepatch and
kretfunc coexist)
- keep a reference to the mm, in case the task is dead
- mptcp: fix deadlock in fastopen error path
- netfilter:
- nf_tables: perform type checking for existing sets
- nf_tables: honor set timeout and garbage collection updates
- ipset: fix hash:net,port,net hang with /0 subnet
- ipset: avoid hung task warning when adding/deleting entries
- selftests: net:
- fix cmsg_so_mark.sh test hang on non-x86 systems
- fix the arp_ndisc_evict_nocarrier test for IPv6
- usb: rndis_host: secure rndis_query check against int overflow
- eth: r8169: fix dmar pte write access during suspend/resume with
WOL
- eth: lan966x: fix configuration of the PCS
- eth: sparx5: fix reading of the MAC address
- eth: qed: allow sleep in qed_mcp_trace_dump()
- eth: hns3:
- fix interrupts re-initialization after VF FLR
- fix handling of promisc when MAC addr table gets full
- refine the handling for VF heartbeat
- eth: mlx5:
- properly handle ingress QinQ-tagged packets on VST
- fix io_eq_size and event_eq_size params validation on big endian
- fix RoCE setting at HCA level if not supported at all
- don't turn CQE compression on by default for IPoIB
- eth: ena:
- fix toeplitz initial hash key value
- account for the number of XDP-processed bytes in interface stats
- fix rx_copybreak value update
Misc:
- ethtool: harden phy stat handling against buggy drivers
- docs: netdev: convert maintainer's doc from FAQ to a normal
document"
* tag 'net-6.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (112 commits)
caif: fix memory leak in cfctrl_linkup_request()
inet: control sockets should not use current thread task_frag
net/ulp: prevent ULP without clone op from entering the LISTEN status
qed: allow sleep in qed_mcp_trace_dump()
MAINTAINERS: Update maintainers for ptp_vmw driver
usb: rndis_host: Secure rndis_query check against int overflow
net: dpaa: Fix dtsec check for PCS availability
octeontx2-pf: Fix lmtst ID used in aura free
drivers/net/bonding/bond_3ad: return when there's no aggregator
netfilter: ipset: Rework long task execution when adding/deleting entries
netfilter: ipset: fix hash:net,port,net hang with /0 subnet
net: sparx5: Fix reading of the MAC address
vxlan: Fix memory leaks in error path
net: sched: htb: fix htb_classify() kernel-doc
net: sched: cbq: dont intepret cls results when asked to drop
net: sched: atm: dont intepret cls results when asked to drop
dt-bindings: net: marvell,orion-mdio: Fix examples
dt-bindings: net: sun8i-emac: Add phy-supply property
net: ipa: use proper endpoint mask for suspend
selftests: net: return non-zero for failures reported in arp_ndisc_evict_nocarrier
...
In the compressed instruction extension, c.jr, c.jalr, c.mv, and c.add
is encoded the following way (each instruction is 16b):
---+-+-----------+-----------+--
100 0 rs1[4:0]!=0 00000 10 : c.jr
100 1 rs1[4:0]!=0 00000 10 : c.jalr
100 0 rd[4:0]!=0 rs2[4:0]!=0 10 : c.mv
100 1 rd[4:0]!=0 rs2[4:0]!=0 10 : c.add
The following logic is used to decode c.jr and c.jalr:
insn & 0xf007 == 0x8002 => instruction is an c.jr
insn & 0xf007 == 0x9002 => instruction is an c.jalr
When 0xf007 is used to mask the instruction, c.mv can be incorrectly
decoded as c.jr, and c.add as c.jalr.
Correct the decoding by changing the mask from 0xf007 to 0xf07f.
Fixes: c22b0bcb1d ("riscv: Add kprobes supported")
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Guo Ren <guoren@kernel.org>
Link: https://lore.kernel.org/r/20230102160748.1307289-1-bjorn@kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Although the powerpc linker script mentions .comment in the DISCARD
section, that has never actually caused it to be discarded, because the
earlier ELF_DETAILS macro (previously STABS_DEBUG) explicitly includes
.comment.
However commit 99cb0d917f ("arch: fix broken BuildID for arm64 and
riscv") introduced an earlier use of DISCARD as part of the RO_DATA
macro. With binutils < 2.36 that causes the DISCARD directives later in
the script to be applied earlier, causing .comment to actually be
discarded.
It's confusing to explicitly include and discard .comment, and even more
so if the behaviour depends on the toolchain version. So don't discard
.comment in order to maintain the existing behaviour in all cases.
Fixes: 83a092cf95 ("powerpc: Link warning for orphan sections")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230105132349.384666-3-mpe@ellerman.id.au
Relocatable kernels must not discard relocations, they need to be
processed at runtime. As such they are included for CONFIG_RELOCATABLE
builds in the powerpc linker script (line 340).
However they are also unconditionally discarded later in the
script (line 414). Previously that worked because the earlier inclusion
superseded the discard.
However commit 99cb0d917f ("arch: fix broken BuildID for arm64 and
riscv") introduced an earlier use of DISCARD as part of the RO_DATA
macro (line 137). With binutils < 2.36 that causes the DISCARD
directives later in the script to be applied earlier, causing .rela* to
actually be discarded at link time, leading to build warnings and a
kernel that doesn't boot:
ld: warning: discarding dynamic section .rela.init.rodata
Fix it by conditionally discarding .rela* only when CONFIG_RELOCATABLE
is disabled.
Fixes: 99cb0d917f ("arch: fix broken BuildID for arm64 and riscv")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230105132349.384666-2-mpe@ellerman.id.au
The powerpc linker script explicitly includes .exit.text, because
otherwise the link fails due to references from __bug_table and
__ex_table. The code is freed (discarded) at runtime along with
.init.text and data.
That has worked in the past despite powerpc not defining
RUNTIME_DISCARD_EXIT because DISCARDS appears late in the powerpc linker
script (line 410), and the explicit inclusion of .exit.text
earlier (line 280) supersedes the discard.
However commit 99cb0d917f ("arch: fix broken BuildID for arm64 and
riscv") introduced an earlier use of DISCARD as part of the RO_DATA
macro (line 136). With binutils < 2.36 that causes the DISCARD
directives later in the script to be applied earlier [1], causing
.exit.text to actually be discarded at link time, leading to build
errors:
'.exit.text' referenced in section '__bug_table' of crypto/algboss.o: defined in
discarded section '.exit.text' of crypto/algboss.o
'.exit.text' referenced in section '__ex_table' of drivers/nvdimm/core.o: defined in
discarded section '.exit.text' of drivers/nvdimm/core.o
Fix it by defining RUNTIME_DISCARD_EXIT, which causes the generic
DISCARDS macro to not include .exit.text at all.
1: https://lore.kernel.org/lkml/87fscp2v7k.fsf@igel.home/
Fixes: 99cb0d917f ("arch: fix broken BuildID for arm64 and riscv")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230105132349.384666-1-mpe@ellerman.id.au
If memory has been found early_init_dt_scan_memory now returns 1. If
it hasn't found any memory it will return 0, allowing other memory
setup mechanisms to carry on.
Previously early_init_dt_scan_memory always returned 0 without
distinguishing between any kind of memory setup being done or not. Any
code path after the early_init_dt_scan memory call in the ramips
plat_mem_setup code wouldn't be executed anymore. Making
early_init_dt_scan_memory the only way to initialize the memory.
Some boards, including my mt7621 based Cudy X6 board, depend on memory
initialization being done via the soc_info.mem_detect function
pointer. Those wouldn't be able to obtain memory and panic the kernel
during early bootup with the message "early_init_dt_alloc_memory_arch:
Failed to allocate 12416 bytes align=0x40".
Fixes: 1f012283e9 ("of/fdt: Rework early_init_dt_scan_memory() to call directly")
Cc: stable@vger.kernel.org
Signed-off-by: Andreas Rammhold <andreas@rammhold.de>
Link: https://lore.kernel.org/r/20221223112748.2935235-1-andreas@rammhold.de
Signed-off-by: Rob Herring <robh@kernel.org>
Both <linux/mmiotrace.h> and <asm/insn-eval.h> define various MMIO_ enum constants,
whose namespace overlaps.
Rename the <asm/insn-eval.h> ones to have a INSN_ prefix, so that the headers can be
used from the same source file.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230101162910.710293-2-Jason@zx2c4.com
After
b3e34a47f9 ("x86/kexec: fix memory leak of elf header buffer"),
freeing image->elf_headers in the error path of crash_load_segments()
is not needed because kimage_file_post_load_cleanup() will take
care of that later. And not clearing it could result in a double-free.
Drop the superfluous vfree() call at the error path of
crash_load_segments().
Fixes: b3e34a47f9 ("x86/kexec: fix memory leak of elf header buffer")
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Baoquan He <bhe@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20221122115122.13937-1-tiwai@suse.de
Pull perf fixes from Borislav Petkov:
- Pass only an initialized perf event attribute to the LSM hook
- Fix a use-after-free on the perf syscall's error path
- A potential integer overflow fix in amd_core_pmu_init()
- Fix the cgroup events tracking after the context handling rewrite
- Return the proper value from the inherit_event() function on error
* tag 'perf_urgent_for_v6.2_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Call LSM hook after copying perf_event_attr
perf: Fix use-after-free in error path
perf/x86/amd: fix potential integer overflow on shift of a int
perf/core: Fix cgroup events tracking
perf core: Return error pointer if inherit_event() fails to find pmu_ctx
Pull x86 fixes from Borislav Petkov:
- Two fixes to correct how kprobes handles INT3 now that they're added
by other functionality like the rethunks and not only kgdb
- Remove __init section markings of two functions which are referenced
by a function in the .text section
* tag 'x86_urgent_for_v6.2_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/kprobes: Fix optprobe optimization check with CONFIG_RETHUNK
x86/kprobes: Fix kprobes instruction boudary check with CONFIG_RETHUNK
x86/calldepth: Fix incorrect init section references
The SM4 CCM/GCM assembly functions for encryption and decryption is
called via indirect function calls. Therefore they need to use
SYM_TYPED_FUNC_START instead of SYM_FUNC_START to cause its type hash
to be emitted when the kernel is built with CONFIG_CFI_CLANG=y.
Otherwise, the code crashes with a CFI failure (if the compiler didn't
happen to optimize out the indirect call).
Fixes: 67fa3a7fdf ("crypto: arm64/sm4 - add CE implementation for CCM mode")
Fixes: ae1b83c7d5 ("crypto: arm64/sm4 - add CE implementation for GCM mode")
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
x86:
* several fixes to nested VMX execution controls
* fixes and clarification to the documentation for Xen emulation
* do not unnecessarily release a pmu event with zero period
* MMU fixes
* fix Coverity warning in kvm_hv_flush_tlb()
selftests:
* fixes for the ucall mechanism in selftests
* other fixes mostly related to compilation with clang
While KVM_XEN_EVTCHN_RESET is usually called with no vCPUs running,
if that happened it could cause a deadlock. This is due to
kvm_xen_eventfd_reset() doing a synchronize_srcu() inside
a kvm->lock critical section.
To avoid this, first collect all the evtchnfd objects in an
array and free all of them once the kvm->lock critical section
is over and th SRCU grace period has expired.
Reported-by: Michal Luczaj <mhal@rbox.co>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Since the CONFIG_RETHUNK and CONFIG_SLS will use INT3 for stopping
speculative execution after function return, kprobe jump optimization
always fails on the functions with such INT3 inside the function body.
(It already checks the INT3 padding between functions, but not inside
the function)
To avoid this issue, as same as kprobes, check whether the INT3 comes
from kgdb or not, and if so, stop decoding and make it fail. The other
INT3 will come from CONFIG_RETHUNK/CONFIG_SLS and those can be
treated as a one-byte instruction.
Fixes: e463a09af2 ("x86: Add straight-line-speculation mitigation")
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/167146051929.1374301.7419382929328081706.stgit@devnote3
Since the CONFIG_RETHUNK and CONFIG_SLS will use INT3 for stopping
speculative execution after RET instruction, kprobes always failes to
check the probed instruction boundary by decoding the function body if
the probed address is after such sequence. (Note that some conditional
code blocks will be placed after function return, if compiler decides
it is not on the hot path.)
This is because kprobes expects kgdb puts the INT3 as a software
breakpoint and it will replace the original instruction.
But these INT3 are not such purpose, it doesn't need to recover the
original instruction.
To avoid this issue, kprobes checks whether the INT3 is owned by
kgdb or not, and if so, stop decoding and make it fail. The other
INT3 will come from CONFIG_RETHUNK/CONFIG_SLS and those can be
treated as a one-byte instruction.
Fixes: e463a09af2 ("x86: Add straight-line-speculation mitigation")
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/167146051026.1374301.392728975473572291.stgit@devnote3
The addition of callthunks_translate_call_dest means that
skip_addr() and patch_dest() can no longer be discarded
as part of the __init section freeing:
WARNING: modpost: vmlinux.o: section mismatch in reference: callthunks_translate_call_dest.cold (section: .text.unlikely) -> skip_addr (section: .init.text)
WARNING: modpost: vmlinux.o: section mismatch in reference: callthunks_translate_call_dest.cold (section: .text.unlikely) -> patch_dest (section: .init.text)
WARNING: modpost: vmlinux.o: section mismatch in reference: is_callthunk.cold (section: .text.unlikely) -> skip_addr (section: .init.text)
ERROR: modpost: Section mismatches detected.
Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.
Fixes: b2e9dfe54b ("x86/bpf: Emit call depth accounting if required")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20221215164334.968863-1-arnd@kernel.org
These are (uint64_t)-1 magic values are a userspace ABI, allowing the
shared info pages and other enlightenments to be disabled. This isn't
a Xen ABI because Xen doesn't let the guest turn these off except with
the full SHUTDOWN_soft_reset mechanism. Under KVM, the userspace VMM is
expected to handle soft reset, and tear down the kernel parts of the
enlightenments accordingly.
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20221226120320.1125390-5-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The evtchnfd structure itself must be protected by either kvm->lock or
SRCU. Use the former in kvm_xen_eventfd_update(), since the lock is
being taken anyway; kvm_xen_hcall_evtchn_send() instead is a reader and
does not need kvm->lock, and is called in SRCU critical section from the
kvm_x86_handle_exit function.
It is also important to use rcu_read_{lock,unlock}() in
kvm_xen_hcall_evtchn_send(), because idr_remove() will *not*
use synchronize_srcu() to wait for readers to complete.
Remove a superfluous if (kvm) check before calling synchronize_srcu()
in kvm_xen_eventfd_deassign() where kvm has been dereferenced already.
Co-developed-by: Michal Luczaj <mhal@rbox.co>
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20221226120320.1125390-3-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In particular, we shouldn't assume that being contiguous in guest virtual
address space means being contiguous in guest *physical* address space.
In dropping the manual calls to kvm_mmu_gva_to_gpa_system(), also drop
the srcu_read_lock() that was around them. All call sites are reached
from kvm_xen_hypercall() which is called from the handle_exit function
with the read lock already held.
536395260 ("KVM: x86/xen: handle PV timers oneshot mode")
1a65105a5 ("KVM: x86/xen: handle PV spinlocks slowpath")
Fixes: 2fd6df2f2 ("KVM: x86/xen: intercept EVTCHNOP_send from guests")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20221226120320.1125390-2-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
