Thomas Gleixner [Fri, 15 Oct 2021 01:16:06 +0000 (03:16 +0200)]
x86/fpu: Do not inherit FPU context for kernel and IO worker threads
BugLink: https://bugs.launchpad.net/bugs/1967750
There is no reason why kernel and IO worker threads need a full clone of
the parent's FPU state. Both are kernel threads which are not supposed to
use FPU. So copying a large state or doing XSAVE() is pointless. Just clean
out the minimally required state for those tasks.
Thomas Gleixner [Fri, 15 Oct 2021 01:16:04 +0000 (03:16 +0200)]
x86/process: Clone FPU in copy_thread()
BugLink: https://bugs.launchpad.net/bugs/1967750
There is no reason to clone FPU in arch_dup_task_struct(). Quite the
contrary - it prevents optimizations. Move it to copy_thread().
Thomas Gleixner [Fri, 15 Oct 2021 01:16:02 +0000 (03:16 +0200)]
x86/fpu: Remove pointless memset in fpu_clone()
BugLink: https://bugs.launchpad.net/bugs/1967750
Zeroing the forked task's FPU registers buffer to avoid leaking init
optimized stale data into the clone is a pointless exercise for the case
where the current task has TIF_NEED_FPU_LOAD set. In that case, the FPU
registers state is copied from current's FPU register buffer which can
contain stale init optimized data as well.
The alledged information leak is non-existant because this stale init
optimized data is used nowhere and cannot leak anywhere.
Thomas Gleixner [Fri, 15 Oct 2021 01:15:59 +0000 (03:15 +0200)]
x86/fpu: Restrict xsaves()/xrstors() to independent states
BugLink: https://bugs.launchpad.net/bugs/1967750
These interfaces are really only valid for features which are independently
managed and not part of the task context state for various reasons.
Tighten the checks and adjust the misleading comments.
Thomas Gleixner [Fri, 15 Oct 2021 01:15:57 +0000 (03:15 +0200)]
x86/pkru: Remove useless include
BugLink: https://bugs.launchpad.net/bugs/1967750
PKRU code does not need anything from FPU headers. Include cpufeature.h
instead and fixup the resulting fallout in perf.
This is a preparation for FPU changes in order to prevent recursive include
hell.
Thomas Gleixner [Fri, 15 Oct 2021 01:15:56 +0000 (03:15 +0200)]
x86/fpu: Update stale comments
BugLink: https://bugs.launchpad.net/bugs/1967750
copy_fpstate_to_sigframe() does not have a slow path anymore. Neither does
the !ia32 restore in __fpu_restore_sig().
Thomas Gleixner [Wed, 8 Sep 2021 13:29:38 +0000 (15:29 +0200)]
x86/fpu/signal: Change return type of __fpu_restore_sig() to boolean
BugLink: https://bugs.launchpad.net/bugs/1967750
Now that fpu__restore_sig() returns a boolean get rid of the individual
error codes in __fpu_restore_sig() as well.
Thomas Gleixner [Wed, 8 Sep 2021 13:29:37 +0000 (15:29 +0200)]
x86/fpu/signal: Change return type of fpu__restore_sig() to boolean
BugLink: https://bugs.launchpad.net/bugs/1967750
None of the call sites cares about the error code. All they need to know is
whether the function succeeded or not.
Thomas Gleixner [Wed, 8 Sep 2021 13:29:34 +0000 (15:29 +0200)]
x86/fpu/signal: Change return type of copy_fpregs_to_sigframe() helpers to boolean
BugLink: https://bugs.launchpad.net/bugs/1967750
Now that copy_fpregs_to_sigframe() returns boolean the individual return
codes in the related helper functions do not make sense anymore. Change
them to return boolean success/fail.
Thomas Gleixner [Wed, 8 Sep 2021 13:29:32 +0000 (15:29 +0200)]
x86/fpu/signal: Change return type of copy_fpstate_to_sigframe() to boolean
BugLink: https://bugs.launchpad.net/bugs/1967750
None of the call sites cares about the actual return code. Change the
return type to boolean and return 'true' on success.
Thomas Gleixner [Wed, 8 Sep 2021 13:29:30 +0000 (15:29 +0200)]
x86/fpu/signal: Move xstate clearing out of copy_fpregs_to_sigframe()
BugLink: https://bugs.launchpad.net/bugs/1967750
When the direct saving of the FPU registers to the user space sigframe
fails, copy_fpregs_to_sigframe() attempts to clear the user buffer.
The most likely reason for such a fail is a page fault. As
copy_fpregs_to_sigframe() is invoked with pagefaults disabled the chance
that __clear_user() succeeds is minuscule.
Move the clearing out into the caller which replaces the
fault_in_pages_writeable() in that error handling path.
The return value confusion will be cleaned up separately.
Thomas Gleixner [Wed, 8 Sep 2021 13:29:26 +0000 (15:29 +0200)]
x86/fpu/signal: Clarify exception handling in restore_fpregs_from_user()
BugLink: https://bugs.launchpad.net/bugs/1967750
FPU restore from a signal frame can trigger various exceptions. The
exceptions are caught with an exception table entry. The handler of this
entry stores the trap number in EAX. The FPU specific fixup negates that
trap number to convert it into an negative error code.
Any other exception than #PF is fatal and recovery is not possible. This
relies on the fact that the #PF exception number is the same as EFAULT, but
that's not really obvious.
Remove the negation from the exception fixup as it really has no value and
check for X86_TRAP_PF at the call site.
There is still confusion due to the return code conversion for the error
case which will be cleaned up separately.
Thomas Gleixner [Wed, 8 Sep 2021 13:29:24 +0000 (15:29 +0200)]
x86/extable: Remove EX_TYPE_FAULT from MCE safe fixups
BugLink: https://bugs.launchpad.net/bugs/1967750
Now that the MC safe copy and FPU have been converted to use the MCE safe
fixup types remove EX_TYPE_FAULT from the list of types which MCE considers
to be safe to be recovered in kernel.
This removes the SGX exception handling of ENCLS from the #MC safe
handling, but according to the SGX wizards the current SGX implementations
cannot survive #MC on ENCLS:
The code relies on the trap number being stored if ENCLS raised an
exception. That's still working, but it does no longer trick the MCE code
into assuming that #MC is handled correctly for ENCLS.
Thomas Gleixner [Wed, 8 Sep 2021 13:29:23 +0000 (15:29 +0200)]
x86/fpu: Use EX_TYPE_FAULT_MCE_SAFE for exception fixups
BugLink: https://bugs.launchpad.net/bugs/1967750
The macros used for restoring FPU state from a user space buffer can handle
all exceptions including #MC. They need to return the trap number in the
error case as the code which invokes them needs to distinguish the cause of
the failure. It aborts the operation for anything except #PF.
Use the new EX_TYPE_FAULT_MCE_SAFE exception table fixup type to document
the nature of the fixup.
Thomas Gleixner [Wed, 8 Sep 2021 13:29:21 +0000 (15:29 +0200)]
x86/copy_mc: Use EX_TYPE_DEFAULT_MCE_SAFE for exception fixups
BugLink: https://bugs.launchpad.net/bugs/1967750
Nothing in that code uses the trap number which was stored by the exception
fixup which is instantiated via _ASM_EXTABLE_FAULT().
Use _ASM_EXTABLE(... EX_TYPE_DEFAULT_MCE_SAFE) instead which just handles
the IP fixup and the type indicates to the #MC handler that the call site
can handle the abort caused by #MC correctly.
Thomas Gleixner [Wed, 8 Sep 2021 13:29:19 +0000 (15:29 +0200)]
x86/extable: Provide EX_TYPE_DEFAULT_MCE_SAFE and EX_TYPE_FAULT_MCE_SAFE
BugLink: https://bugs.launchpad.net/bugs/1967750
Provide exception fixup types which can be used to identify fixups which
allow in kernel #MC recovery and make them invoke the existing handlers.
These will be used at places where #MC recovery is handled correctly by the
caller.
Thomas Gleixner [Wed, 8 Sep 2021 13:29:18 +0000 (15:29 +0200)]
x86/extable: Rework the exception table mechanics
BugLink: https://bugs.launchpad.net/bugs/1967750
The exception table entries contain the instruction address, the fixup
address and the handler address. All addresses are relative. Storing the
handler address has a few downsides:
1) Most handlers need to be exported
2) Handlers can be defined everywhere and there is no overview about the
handler types
3) MCE needs to check the handler type to decide whether an in kernel #MC
can be recovered. The functionality of the handler itself is not in any
way special, but for these checks there need to be separate functions
which in the worst case have to be exported.
Some of these 'recoverable' exception fixups are pretty obscure and
just reuse some other handler to spare code. That obfuscates e.g. the
#MC safe copy functions. Cleaning that up would require more handlers
and exports
Rework the exception fixup mechanics by storing a fixup type number instead
of the handler address and invoke the proper handler for each fixup
type. Also teach the extable sort to leave the type field alone.
This makes most handlers static except for special cases like the MCE
MSR fixup and the BPF fixup. This allows to add more types for cleaning up
the obscure places without adding more handler code and exports.
There is a marginal code size reduction for a production config and it
removes _eight_ exported symbols.
netfilter: nf_tables: initialize registers in nft_do_chain()
Initialize registers to avoid stack leak into userspace.
Fixes: 96518518cc41 ("netfilter: add nftables") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
(cherry picked from commit 4c905f6740a365464e91467aa50916555b28213d)
CVE-2022-1016 Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Acked-by: Tim Gardner <tim.gardner@canonical.com> Acked-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
netfilter: nf_tables: validate registers coming from userspace.
Bail out in case userspace uses unsupported registers.
Fixes: 49499c3e6e18 ("netfilter: nf_tables: switch registers to 32 bit addressing") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
(cherry picked from commit 6e1acfa387b9ff82cfc7db8cc3b6959221a95851)
CVE-2022-1015 Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Acked-by: Tim Gardner <tim.gardner@canonical.com> Acked-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
nfc: st21nfca: Fix potential buffer overflows in EVT_TRANSACTION
It appears that there are some buffer overflows in EVT_TRANSACTION.
This happens because the length parameters that are passed to memcpy
come directly from skb->data and are not guarded in any way.
Signed-off-by: Jordy Zomer <jordy@pwning.systems> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 4fbcc1a4cb20fe26ad0225679c536c80f1648221)
CVE-2022-26490 Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Acked-by: Bartlomiej Zolnierkiewicz <bartlomiej.zolnierkiewicz@canonical.com> Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Peter Zijlstra [Tue, 26 Oct 2021 12:01:48 +0000 (14:01 +0200)]
bpf,x86: Respect X86_FEATURE_RETPOLINE*
BugLink: https://bugs.launchpad.net/bugs/1967579
Current BPF codegen doesn't respect X86_FEATURE_RETPOLINE* flags and
unconditionally emits a thunk call, this is sub-optimal and doesn't
match the regular, compiler generated, code.
Update the i386 JIT to emit code equal to what the compiler emits for
the regular kernel text (IOW. a plain THUNK call).
Update the x86_64 JIT to emit code similar to the result of compiler
and kernel rewrites as according to X86_FEATURE_RETPOLINE* flags.
Inlining RETPOLINE_AMD (lfence; jmp *%reg) and !RETPOLINE (jmp *%reg),
while doing a THUNK call for RETPOLINE.
This removes the hard-coded retpoline thunks and shrinks the generated
code. Leaving a single retpoline thunk definition in the kernel.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20211026120310.614772675@infradead.org
(backported from commit 87c87ecd00c54ecd677798cb49ef27329e0fab41)
[cascardo: RETPOLINE_AMD was renamed to RETPOLINE_LFENCE] Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Peter Zijlstra [Tue, 26 Oct 2021 12:01:47 +0000 (14:01 +0200)]
bpf,x86: Simplify computing label offsets
BugLink: https://bugs.launchpad.net/bugs/1967579
Take an idea from the 32bit JIT, which uses the multi-pass nature of
the JIT to compute the instruction offsets on a prior pass in order to
compute the relative jump offsets on a later pass.
Application to the x86_64 JIT is slightly more involved because the
offsets depend on program variables (such as callee_regs_used and
stack_depth) and hence the computed offsets need to be kept in the
context of the JIT.
This removes, IMO quite fragile, code that hard-codes the offsets and
tries to compute the length of variable parts of it.
Convert both emit_bpf_tail_call_*() functions which have an out: label
at the end. Additionally emit_bpt_tail_call_direct() also has a poke
table entry, for which it computes the offset from the end (and thus
already relies on the previous pass to have computed addrs[i]), also
convert this to be a forward based offset.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20211026120310.552304864@infradead.org
(cherry picked from commit dceba0817ca329868a15e2e1dd46eb6340b69206) Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Specifically, the sequence above is 5 bytes for the low 8 registers,
but 6 bytes for the high 8 registers. This means that unless the
compilers prefix stuff the call with higher registers this replacement
will fail.
Luckily GCC strongly favours RAX for the indirect calls and most (95%+
for defconfig-x86_64) will be converted. OTOH clang strongly favours
R11 and almost nothing gets converted.
Note: it will also generate a correct replacement for the Jcc.d32
case, except unless the compilers start to prefix stuff that, it'll
never fit. Specifically:
Jncc.d8 1f
LFENCE
JMP *%\reg
1:
is 7-8 bytes long, where the original instruction in unpadded form is
only 6 bytes.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20211026120310.359986601@infradead.org
(backported from commit bbe2df3f6b6da7848398d55b1311d58a16ec21e4)
[cascardo: RETPOLINE_AMD was renamed to RETPOLINE_LFENCE] Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Peter Zijlstra [Tue, 26 Oct 2021 12:01:42 +0000 (14:01 +0200)]
x86/alternative: Implement .retpoline_sites support
BugLink: https://bugs.launchpad.net/bugs/1967579
Rewrite retpoline thunk call sites to be indirect calls for
spectre_v2=off. This ensures spectre_v2=off is as near to a
RETPOLINE=n build as possible.
This is the replacement for objtool writing alternative entries to
ensure the same and achieves feature-parity with the previous
approach.
One noteworthy feature is that it relies on the thunks to be in
machine order to compute the register index.
Specifically, this does not yet address the Jcc __x86_indirect_thunk_*
calls generated by clang, a future patch will add this.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20211026120310.232495794@infradead.org
(backported from commit 7508500900814d14e2e085cdc4e28142721abbdf)
[cascardo: small conflict fixup at arch/x86/kernel/module.c] Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Peter Zijlstra [Tue, 26 Oct 2021 12:01:41 +0000 (14:01 +0200)]
x86/retpoline: Create a retpoline thunk array
BugLink: https://bugs.launchpad.net/bugs/1967579
Stick all the retpolines in a single symbol and have the individual
thunks as inner labels, this should guarantee thunk order and layout.
Previously there were 16 (or rather 15 without rsp) separate symbols and
a toolchain might reasonably expect it could displace them however it
liked, with disregard for their relative position.
However, now they're part of a larger symbol. Any change to their
relative position would disrupt this larger _array symbol and thus not
be sound.
This is the same reasoning used for data symbols. On their own there
is no guarantee about their relative position wrt to one aonther, but
we're still able to do arrays because an array as a whole is a single
larger symbol.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20211026120310.169659320@infradead.org
(cherry picked from commit 1a6f74429c42a3854980359a758e222005712aee) Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Peter Zijlstra [Tue, 26 Oct 2021 12:01:39 +0000 (14:01 +0200)]
x86/asm: Fixup odd GEN-for-each-reg.h usage
BugLink: https://bugs.launchpad.net/bugs/1967579
Currently GEN-for-each-reg.h usage leaves GEN defined, relying on any
subsequent usage to start with #undef, which is rude.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20211026120310.041792350@infradead.org
(cherry picked from commit b6d3d9944bd7c9e8c06994ead3c9952f673f2a66) Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Peter Zijlstra [Tue, 26 Oct 2021 12:01:38 +0000 (14:01 +0200)]
x86/asm: Fix register order
BugLink: https://bugs.launchpad.net/bugs/1967579
Ensure the register order is correct; this allows for easy translation
between register number and trampoline and vice-versa.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20211026120309.978573921@infradead.org
(cherry picked from commit a92ede2d584a2e070def59c7e47e6b6f6341c55c) Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Peter Zijlstra [Tue, 26 Oct 2021 12:01:37 +0000 (14:01 +0200)]
x86/retpoline: Remove unused replacement symbols
BugLink: https://bugs.launchpad.net/bugs/1967579
Now that objtool no longer creates alternatives, these replacement
symbols are no longer needed, remove them.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20211026120309.915051744@infradead.org
(cherry picked from commit 4fe79e710d9574a14993f8b4e16b7252da72d5e8) Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Peter Zijlstra [Tue, 26 Oct 2021 12:01:36 +0000 (14:01 +0200)]
objtool,x86: Replace alternatives with .retpoline_sites
BugLink: https://bugs.launchpad.net/bugs/1967579
Instead of writing complete alternatives, simply provide a list of all
the retpoline thunk calls. Then the kernel is free to do with them as
it pleases. Simpler code all-round.
Peter Zijlstra [Tue, 26 Oct 2021 12:01:35 +0000 (14:01 +0200)]
objtool: Shrink struct instruction
BugLink: https://bugs.launchpad.net/bugs/1967579
Any one instruction can only ever call a single function, therefore
insn->mcount_loc_node is superfluous and can use insn->call_node.
This shrinks struct instruction, which is by far the most numerous
structure objtool creates.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20211026120309.785456706@infradead.org
(cherry picked from commit c509331b41b7365e17396c246e8c5797bccc8074) Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Peter Zijlstra [Tue, 26 Oct 2021 12:01:34 +0000 (14:01 +0200)]
objtool: Explicitly avoid self modifying code in .altinstr_replacement
BugLink: https://bugs.launchpad.net/bugs/1967579
Assume ALTERNATIVE()s know what they're doing and do not change, or
cause to change, instructions in .altinstr_replacement sections.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20211026120309.722511775@infradead.org
(cherry picked from commit dd003edeffa3cb87bc9862582004f405d77d7670) Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Peter Zijlstra [Tue, 26 Oct 2021 12:01:33 +0000 (14:01 +0200)]
objtool: Classify symbols
BugLink: https://bugs.launchpad.net/bugs/1967579
In order to avoid calling str*cmp() on symbol names, over and over, do
them all once upfront and store the result.
This commit seems to break certain SCSI drivers, causing I/O errors and
filesystem corruption. This problem can be systematically reproduced on
a power9 box with an aacraid controller.
Reverting this one seems the safest solution for now, until we find more
details about the real problem.
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
thermal: int340x: Update OS policy capability handshake
BugLink: https://bugs.launchpad.net/bugs/1966089
Update the firmware with OS supported policies mask, so that firmware can
relinquish its internal controls. Without this update several Tiger Lake
laptops gets performance limited with in few seconds of executing in
turbo region.
The existing way of enumerating firmware policies via IDSP method and
selecting policy by directly writing those policy UUIDS via _OSC method
is not supported in newer generation of hardware.
There is a new UUID "B23BA85D-C8B7-3542-88DE-8DE2FFCFD698" is defined for
updating policy capabilities. As part of ACPI _OSC method:
DWORD1: As defined in the ACPI 5.0 Specification
- Bit 0: Query Flag
- Bits 1-3: Always 0
- Bits 4-31: Reserved
DWORD2 and beyond:
- Bit0: set to 1 to indicate Intel(R) Dynamic Tuning is active, 0 to
indicate it is disabled and legacy thermal mechanism should
be enabled.
- Bit1: set to 1 to indicate Intel(R) Dynamic Tuning is controlling
active cooling, 0 to indicate bios shall enable legacy thermal
zone with active trip point.
- Bit2: set to 1 to indicate Intel(R) Dynamic Tuning is controlling
passive cooling, 0 to indicate bios shall enable legacy thermal
zone with passive trip point.
- Bit3: set to 1 to indicate Intel(R) Dynamic Tuning is handling
critical trip point, 0 to indicate bios shall enable legacy
thermal zone with critical trip point.
- Bits 4:31: Reserved
From sysfs interface, there is an existing interface to update policy
UUID using attribute "current_uuid". User space can write the same UUID
for ACTIVE, PASSIVE and CRITICAL policy. Driver converts these UUIDs to
DWORD2 Bit 1 to Bit 3. When any of the policy is activated by user
space it is assumed that dynamic tuning is active.
For example
$cd /sys/bus/platform/devices/INTC1040:00/uuids
To support active policy
$echo "3A95C389-E4B8-4629-A526-C52C88626BAE" > current_uuid
To support passive policy
$echo "42A441D6-AE6A-462b-A84B-4A8CE79027D3" > current_uuid
To support critical policy
$echo "97C68AE7-15FA-499c-B8C9-5DA81D606E0A" > current_uuid
To match the bit format for DWORD2, rearranged enum int3400_thermal_uuid
and int3400_thermal_uuids[] by swapping current INT3400_THERMAL_ACTIVE
and INT3400_THERMAL_PASSIVE_1.
If the policies are enumerated via IDSP method then legacy method is
used, if not the new method is used to update policy support.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
(cherry picked from commit c7ff29763989bd09c433f73fae3c1e1c15d9cda4) Signed-off-by: Colin Ian King <colin.king@ubuntu.com> Acked-by: Tim Gardner <tim.gardner@canonical.com> Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Commit 5dbbbd01cbba83 ("ice: Avoid RTNL lock when re-creating
auxiliary device") changes a process of re-creation of aux device
so ice_plug_aux_dev() is called from ice_service_task() context.
This unfortunately opens a race window that can result in dead-lock
when interface has left LAG and immediately enters LAG again.
Reproducer:
```
#!/bin/sh
ip link add lag0 type bond mode 1 miimon 100
ip link set lag0
for n in {1..10}; do
echo Cycle: $n
ip link set ens7f0 master lag0
sleep 1
ip link set ens7f0 nomaster
done
```
1. Command 'ip link ... set nomaster' causes that ice_plug_aux_dev()
is called from ice_service_task() context, aux device is created
and associated device->lock is taken.
2. Command 'ip link ... set master...' calls ice's notifier under
RTNL lock and that notifier calls ice_unplug_aux_dev(). That
function tries to take aux device->lock but this is already taken
by ice_plug_aux_dev() in step 1
3. Later ice_plug_aux_dev() tries to take RTNL lock but this is already
taken in step 2
4. Dead-lock
The patch fixes this issue by following changes:
- Bit ICE_FLAG_PLUG_AUX_DEV is kept to be set during ice_plug_aux_dev()
call in ice_service_task()
- The bit is checked in ice_clear_rdma_cap() and only if it is not set
then ice_unplug_aux_dev() is called. If it is set (in other words
plugging of aux device was requested and ice_plug_aux_dev() is
potentially running) then the function only clears the bit
- Once ice_plug_aux_dev() call (in ice_service_task) is finished
the bit ICE_FLAG_PLUG_AUX_DEV is cleared but it is also checked
whether it was already cleared by ice_clear_rdma_cap(). If so then
aux device is unplugged.
Signed-off-by: Ivan Vecera <ivecera@redhat.com> Co-developed-by: Petr Oros <poros@redhat.com> Signed-off-by: Petr Oros <poros@redhat.com> Reviewed-by: Dave Ertman <david.m.ertman@intel.com> Link: https://lore.kernel.org/r/20220310171641.3863659-1-ivecera@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
4e6292114c74 ("x86/paravirt: Add new features for paravirt patching")
there is an ordering dependency between patching paravirt ops and
patching alternatives, the module loader still violates this.
Fixes: 4e6292114c74 ("x86/paravirt: Add new features for paravirt patching") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20220303112825.068773913@infradead.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
The error message when I build vm tests on debian10 (GLIBC 2.28):
userfaultfd.c: In function `userfaultfd_pagemap_test':
userfaultfd.c:1393:37: error: `MADV_PAGEOUT' undeclared (first use
in this function); did you mean `MADV_RANDOM'?
if (madvise(area_dst, test_pgsize, MADV_PAGEOUT))
^~~~~~~~~~~~
MADV_RANDOM
This patch includes these newer definitions from UAPI linux/mman.h, is
useful to fix tests build on systems without these definitions in glibc
sys/mman.h.
Link: https://lkml.kernel.org/r/20220227055330.43087-2-zhouchengming@bytedance.com Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> Reviewed-by: Shuah Khan <skhan@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
Fix an error message and report the correct failing function.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
seqno could be read as a stale value outside of the lock. The lock is
already acquired to protect the modification of seqno against a possible
race condition. Place the reading of this value also inside this locking
to protect it against a possible race condition.
Signed-off-by: Niels Dossche <dossche.niels@gmail.com> Acked-by: Martin Habets <habetsm.xilinx@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
If recv_actor() returns an incorrect value, tcp_read_sock()
might loop forever.
Instead, issue a one time warning and make sure to make progress.
Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/20220302161723.3910001-2-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
The wdev channel information is updated post channel switch only for
the station mode and not for the other modes. Due to this, the P2P client
still points to the old value though it moved to the new channel
when the channel change is induced from the P2P GO.
Update the bss channel after CSA channel switch completion for P2P client
interface as well.
VRR capable property is not attached by default to the connector
It is attached only if VRR is supported.
So if the driver tries to call drm core set prop function without
it being attached that causes NULL dereference.
Cc: Jani Nikula <jani.nikula@intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: dri-devel@lists.freedesktop.org Signed-off-by: Manasi Navare <manasi.d.navare@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220225013055.9282-1-manasi.d.navare@intel.com Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
Some APs misbehave when TWT is used and cause our firmware to crash.
We don't know a reasonable way to detect and work around this problem
in the FW yet. To prevent these crashes, disable TWT in the driver by
stopping to advertise TWT support.
The function ioremap() in fs_init() can fail, so its return value should
be checked.
Reported-by: TOTE Robot <oslab@tsinghua.edu.cn> Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
Register the CAN device only when all the necessary initialization is
completed. This patch makes sure all the data structures and locks are
initialized before registering the CAN device.
Link: https://lore.kernel.org/all/20220221225935.12300-1-prabhakar.mahadev-lad.rj@bp.renesas.com Reported-by: Pavel Machek <pavel@denx.de> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Reviewed-by: Pavel Machek <pavel@denx.de> Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
sent_cmd memory is not freed before freeing hci_dev causing it to leak
it contents.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
Resending this to properly add it to the patch tracker - thanks for letting
me know, Arnd :)
When ARM is enabled, and BITREVERSE is disabled,
Kbuild gives the following warning:
WARNING: unmet direct dependencies detected for HAVE_ARCH_BITREVERSE
Depends on [n]: BITREVERSE [=n]
Selected by [y]:
- ARM [=y] && (CPU_32v7M [=n] || CPU_32v7 [=y]) && !CPU_32v6 [=n]
This is because ARM selects HAVE_ARCH_BITREVERSE
without selecting BITREVERSE, despite
HAVE_ARCH_BITREVERSE depending on BITREVERSE.
This unmet dependency bug was found by Kismet,
a static analysis tool for Kconfig. Please advise if this
is not the appropriate solution.
Signed-off-by: Julian Braha <julianbraha@gmail.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
...for each but CPU 0/boot.
Basic debug printks right before the mentioned line say:
[ 0.048170] CPU: 1, smt_mask:
So smt_mask, which is sibling mask obviously, is empty when entering
the function.
This is critical, as sched_core_cpu_starting() calculates
core-scheduling parameters only once per CPU start, and it's crucial
to have all the parameters filled in at that moment (at least it
uses cpu_smt_mask() which in fact is `&cpu_sibling_map[cpu]` on
MIPS).
A bit of debugging led me to that set_cpu_sibling_map() performing
the actual map calculation, was being invocated after
notify_cpu_start(), and exactly the latter function starts CPU HP
callback round (sched_core_cpu_starting() is basically a CPU HP
callback).
While the flow is same on ARM64 (maps after the notifier, although
before calling set_cpu_online()), x86 started calculating sibling
maps earlier than starting the CPU HP callbacks in Linux 4.14 (see
[0] for the reference). Neither me nor my brief tests couldn't find
any potential caveats in calculating the maps right after performing
delay calibration, but the WARN splat is now gone.
The very same debug prints now yield exactly what I expected from
them:
Signed-off-by: Alexander Lobakin <alobakin@pm.me> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
If an MFP station isn't authorized, the receiver will (or
at least should) drop the action frame since it's a robust
management frame, but if we're not authorized we haven't
installed keys yet. Refuse attempts to start a session as
they'd just time out.
There are signal integrity issues running the eMMC at 200MHz on Puma
RK3399-Q7.
Similar to the work-around found for RK3399 Gru boards, lowering the
frequency to 100MHz made the eMMC much more stable, so let's lower the
frequency to 100MHz.
It might be possible to run at 150MHz as on RK3399 Gru boards but only
100MHz was extensively tested.
Cc: Quentin Schulz <foss+kernel@0leil.net> Signed-off-by: Jakob Unterwurzacher <jakob.unterwurzacher@theobroma-systems.com> Signed-off-by: Quentin Schulz <quentin.schulz@theobroma-systems.com> Link: https://lore.kernel.org/r/20220119134948.1444965-1-quentin.schulz@theobroma-systems.com Signed-off-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
xfrm_migrate cannot handle address family change of an xfrm_state.
The symptons are the xfrm_state will be migrated to a wrong address,
and sending as well as receiving packets wil be broken.
This commit fixes it by breaking the original xfrm_state_clone
method into two steps so as to update the props.family before
running xfrm_init_state. As the result, xfrm_state's inner mode,
outer mode, type and IP header length in xfrm_state_migrate can
be updated with the new address family.
Tested with additions to Android's kernel unit test suite:
https://android-review.googlesource.com/c/kernel/tests/+/1885354
Signed-off-by: Yan Yan <evitayan@google.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
This patch enables distinguishing SAs and SPs based on if_id during
the xfrm_migrate flow. This ensures support for xfrm interfaces
throughout the SA/SP lifecycle.
When there are multiple existing SPs with the same direction,
the same xfrm_selector and different endpoint addresses,
xfrm_migrate might fail with ENODATA.
Specifically, the code path for performing xfrm_migrate is:
Stage 1: find policy to migrate with
xfrm_migrate_policy_find(sel, dir, type, net)
Stage 2: find and update state(s) with
xfrm_migrate_state_find(mp, net)
Stage 3: update endpoint address(es) of template(s) with
xfrm_policy_migrate(pol, m, num_migrate)
Currently "Stage 1" always returns the first xfrm_policy that
matches, and "Stage 3" looks for the xfrm_tmpl that matches the
old endpoint address. Thus if there are multiple xfrm_policy
with same selector, direction, type and net, "Stage 1" might
rertun a wrong xfrm_policy and "Stage 3" will fail with ENODATA
because it cannot find a xfrm_tmpl with the matching endpoint
address.
The fix is to allow userspace to pass an if_id and add if_id
to the matching rule in Stage 1 and Stage 2 since if_id is a
unique ID for xfrm_policy and xfrm_state. For compatibility,
if_id will only be checked if the attribute is set.
Tested with additions to Android's kernel unit test suite:
https://android-review.googlesource.com/c/kernel/tests/+/1668886
Signed-off-by: Yan Yan <evitayan@google.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
The micro USB3.0 port available on the Haikou evaluation kit for Puma
RK3399-Q7 SoM supports dual-role model (aka drd or OTG) but its support
was broken until now because of missing logic around the ID pin.
This adds proper support for USB OTG on Puma Haikou by "connecting" the
GPIO used for USB ID to the USB3 controller device.
This reverts commit 68ac0f3810e76a853b5f7b90601a05c3048b8b54 because ID
0 was meant to be used for configuring the policy/state without
matching for a specific interface (e.g., Cilium is affected, see
https://github.com/cilium/cilium/pull/18789 and
https://github.com/cilium/cilium/pull/19019).
Signed-off-by: Kai Lueke <kailueke@linux.microsoft.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
Commit e2ae38cf3d91 ("vhost: fix hung thread due to erroneous iotlb
entries") tries to reject the IOTLB message whose size is zero. But
the size is not necessarily meaningful, one example is the batching
hint, so the commit breaks that.
Fixing this be reject zero size message only if the message is used to
update/invalidate the IOTLB.
Fixes: e2ae38cf3d91 ("vhost: fix hung thread due to erroneous iotlb entries") Reported-by: Eli Cohen <elic@nvidia.com> Cc: Anirudh Rayabharam <mail@anirudhrb.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20220310075211.4801-1-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Tested-by: Eli Cohen <elic@nvidia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
The above change depends on upstream commit 0faf890fc519 ("net: dsa:
drop rtnl_lock from dsa_slave_switchdev_event_work"), which is not
present in linux-5.15.y. Without that change, waiting for the switchdev
workqueue causes deadlocks on the rtnl_mutex.
Backporting the dependency commit isn't trivial/desirable, since it
requires that the following dependencies of the dependency are also
backported:
df405910ab9f net: dsa: sja1105: wait for dynamic config command completion on writes too eb016afd83a9 net: dsa: sja1105: serialize access to the dynamic config interface 2468346c5677 net: mscc: ocelot: serialize access to the MAC table f7eb4a1c0864 net: dsa: b53: serialize access to the ARL table cf231b436f7c net: dsa: lantiq_gswip: serialize access to the PCE registers 338a3a4745aa net: dsa: introduce locking for the address lists on CPU and DSA ports
and then this bugfix on top:
8940e6b669ca ("net: dsa: avoid call to __dev_set_promiscuity() while rtnl_mutex isn't held")
Reported-by: Daniel Suchy <danny@danysek.cz> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
Drop various include not actually used in genhd.h itself, and
move the remaning includes closer together.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210920123328.1399408-15-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk> Reported-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>a Reported-by: "H. Nikolaus Schaller" <hns@goldelico.com> Reported-by: Guenter Roeck <linux@roeck-us.net> Cc: "Maciej W. Rozycki" <macro@orcam.me.uk>
[ resolves MIPS build failure by luck, root cause needs to be fixed in
Linus's tree properly, but this is needed for now to fix the build - gregkh ] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
Commit 67d96729a9e7 ("riscv: Update Canaan Kendryte K210 device tree")
incorrectly removed two entries from the PLIC interrupt-controller node's
interrupts-extended property.
The PLIC driver cannot know the mapping between hart contexts and hart ids,
so this information has to be provided by device tree, as specified by the
PLIC device tree binding.
The PLIC driver uses the interrupts-extended property, and initializes the
hart context registers in the exact same order as provided by the
interrupts-extended property.
In other words, if we don't specify the S-mode interrupts, the PLIC driver
will simply initialize the hart0 S-mode hart context with the hart1 M-mode
configuration. It is therefore essential to specify the S-mode IRQs even
though the system itself will only ever be running in M-mode.
Re-add the S-mode interrupts, so that we get working IRQs on hart1 again.
On TGL/RKL the BIOS likes to use some kind of bogus DBUF layout
that doesn't match what the spec recommends. With a single active
pipe that is not going to be a problem, but with multiple pipes
active skl_commit_modeset_enables() goes into an infinite loop
since it can't figure out any order in which it can commit the
pipes without causing DBUF overlaps between the planes.
We'd need some kind of extra DBUF defrag stage in between to
make the transition possible. But that is clearly way too complex
a solution, so in the name of simplicity let's just sanitize the
DBUF state by simply turning off all planes when we detect a
pipe encroaching on its neighbours' DBUF slices. We only have
to disable the primary planes as all other planes should have
already been disabled (if they somehow were enabled) by
earlier sanitization steps.
And for good measure let's also sanitize in case the DBUF
allocations of the pipes already seem to overlap each other.
Cc: <stable@vger.kernel.org> # v5.14+ Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/4762 Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220204141818.1900-3-ville.syrjala@linux.intel.com Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
(cherry picked from commit 15512021eb3975a8c2366e3883337e252bb0eee5) Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
We don't allow send and balance/relocation to run in parallel in order
to prevent send failing or silently producing some bad stream. This is
because while send is using an extent (specially metadata) or about to
read a metadata extent and expecting it belongs to a specific parent
node, relocation can run, the transaction used for the relocation is
committed and the extent gets reallocated while send is still using the
extent, so it ends up with a different content than expected. This can
result in just failing to read a metadata extent due to failure of the
validation checks (parent transid, level, etc), failure to find a
backreference for a data extent, and other unexpected failures. Besides
reallocation, there's also a similar problem of an extent getting
discarded when it's unpinned after the transaction used for block group
relocation is committed.
The restriction between balance and send was added in commit 9e967495e0e0
("Btrfs: prevent send failures and crashes due to concurrent relocation"),
kernel 5.3, while the more general restriction between send and relocation
was added in commit 1cea5cf0e664 ("btrfs: ensure relocation never runs
while we have send operations running"), kernel 5.14.
Both send and relocation can be very long running operations. Relocation
because it has to do a lot of IO and expensive backreference lookups in
case there are many snapshots, and send due to read IO when operating on
very large trees. This makes it inconvenient for users and tools to deal
with scheduling both operations.
For zoned filesystem we also have automatic block group relocation, so
send can fail with -EAGAIN when users least expect it or send can end up
delaying the block group relocation for too long. In the future we might
also get the automatic block group relocation for non zoned filesystems.
This change makes it possible for send and relocation to run in parallel.
This is achieved the following way:
1) For all tree searches, send acquires a read lock on the commit root
semaphore;
2) After each tree search, and before releasing the commit root semaphore,
the leaf is cloned and placed in the search path (struct btrfs_path);
3) After releasing the commit root semaphore, the changed_cb() callback
is invoked, which operates on the leaf and writes commands to the pipe
(or file in case send/receive is not used with a pipe). It's important
here to not hold a lock on the commit root semaphore, because if we did
we could deadlock when sending and receiving to the same filesystem
using a pipe - the send task blocks on the pipe because it's full, the
receive task, which is the only consumer of the pipe, triggers a
transaction commit when attempting to create a subvolume or reserve
space for a write operation for example, but the transaction commit
blocks trying to write lock the commit root semaphore, resulting in a
deadlock;
4) Before moving to the next key, or advancing to the next change in case
of an incremental send, check if a transaction used for relocation was
committed (or is about to finish its commit). If so, release the search
path(s) and restart the search, to where we were before, so that we
don't operate on stale extent buffers. The search restarts are always
possible because both the send and parent roots are RO, and no one can
add, remove of update keys (change their offset) in RO trees - the
only exception is deduplication, but that is still not allowed to run
in parallel with send;
5) Periodically check if there is contention on the commit root semaphore,
which means there is a transaction commit trying to write lock it, and
release the semaphore and reschedule if there is contention, so as to
avoid causing any significant delays to transaction commits.
This leaves some room for optimizations for send to have less path
releases and re searching the trees when there's relocation running, but
for now it's kept simple as it performs quite well (on very large trees
with resulting send streams in the order of a few hundred gigabytes).
Test case btrfs/187, from fstests, stresses relocation, send and
deduplication attempting to run in parallel, but without verifying if send
succeeds and if it produces correct streams. A new test case will be added
that exercises relocation happening in parallel with send and then checks
that send succeeds and the resulting streams are correct.
A final note is that for now this still leaves the mutual exclusion
between send operations and deduplication on files belonging to a root
used by send operations. A solution for that will be slightly more complex
but it will eventually be built on top of this change.
Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
Since kprobe_int3_handler() is called in do_int3(), probing do_int3()
can cause a breakpoint recursion and crash the kernel. Therefore,
do_int3() should be marked as NOKPROBE_SYMBOL.
There is a limited amount of SGX memory (EPC) on each system. When that
memory is used up, SGX has its own swapping mechanism which is similar
in concept but totally separate from the core mm/* code. Instead of
swapping to disk, SGX swaps from EPC to normal RAM. That normal RAM
comes from a shared memory pseudo-file and can itself be swapped by the
core mm code. There is a hierarchy like this:
EPC <-> shmem <-> disk
After data is swapped back in from shmem to EPC, the shmem backing
storage needs to be freed. Currently, the backing shmem is not freed.
This effectively wastes the shmem while the enclave is running. The
memory is recovered when the enclave is destroyed and the backing
storage freed.
Sort this out by freeing memory with shmem_truncate_range(), as soon as
a page is faulted back to the EPC. In addition, free the memory for
PCMD pages as soon as all PCMD's in a page have been marked as unused
by zeroing its contents.
Cc: stable@vger.kernel.org Fixes: 1728ab54b4be ("x86/sgx: Add a page reclaimer") Reported-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lkml.kernel.org/r/20220303223859.273187-1-jarkko@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>