commit e6cfcdda8c upstream.
AMD's "Technical Guidance for Mitigating Branch Type Confusion,
Rev. 1.0 2022-07-12" whitepaper, under section 6.1.2 "IBPB On
Privileged Mode Entry / SMT Safety" says:
Similar to the Jmp2Ret mitigation, if the code on the sibling thread
cannot be trusted, software should set STIBP to 1 or disable SMT to
ensure SMT safety when using this mitigation.
So, like already being done for retbleed=unret, and now also for
retbleed=ibpb, force STIBP on machines that have it, and report its SMT
vulnerability status accordingly.
[ bp: Remove the "we" and remove "[AMD]" applicability parameter which
doesn't work here. ]
Fixes: 3ebc170068 ("x86/bugs: Add retbleed=ibpb")
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org # 5.10, 5.15, 5.19
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537
Link: https://lore.kernel.org/r/20220804192201.439596-1-kim.phillips@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2ee73ef60d ]
Change dm-writecache, so that it counts the number of blocks discarded
instead of the number of discard bios. Make it consistent with the
read and write statistics counters that were changed to count the
number of blocks instead of bios.
Fixes: e3a35d0340 ("dm writecache: add event counters")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b2676e1482 ]
Change dm-writecache, so that it counts the number of blocks written
instead of the number of write bios. Bios can be split and requeued
using the dm_accept_partial_bio function, so counting bios caused
inaccurate results.
Fixes: e3a35d0340 ("dm writecache: add event counters")
Reported-by: Yu Kuai <yukuai1@huaweicloud.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2c6e755b49 ]
Change dm-writecache, so that it counts the number of blocks read
instead of the number of read bios. Bios can be split and requeued
using the dm_accept_partial_bio function, so counting bios caused
inaccurate results.
Fixes: e3a35d0340 ("dm writecache: add event counters")
Reported-by: Yu Kuai <yukuai1@huaweicloud.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8bcedb4ce0 ]
When kernel is booted with idle=nomwait do not use MWAIT as the
default idle state.
If the user boots the kernel with idle=nomwait, it is a clear
direction to not use mwait as the default idle state.
However, the current code does not take this into consideration
while selecting the default idle state on x86.
Fix it by checking for the idle=nomwait boot option in
prefer_mwait_c1_over_halt().
Also update the documentation around idle=nomwait appropriately.
[ dhansen: tweak commit message ]
Signed-off-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Link: https://lkml.kernel.org/r/fdc2dc2d0a1bc21c2f53d989ea2d2ee3ccbc0dbe.1654538381.git-series.wyes.karny@amd.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 2b12993220 upstream.
tl;dr: The Enhanced IBRS mitigation for Spectre v2 does not work as
documented for RET instructions after VM exits. Mitigate it with a new
one-entry RSB stuffing mechanism and a new LFENCE.
== Background ==
Indirect Branch Restricted Speculation (IBRS) was designed to help
mitigate Branch Target Injection and Speculative Store Bypass, i.e.
Spectre, attacks. IBRS prevents software run in less privileged modes
from affecting branch prediction in more privileged modes. IBRS requires
the MSR to be written on every privilege level change.
To overcome some of the performance issues of IBRS, Enhanced IBRS was
introduced. eIBRS is an "always on" IBRS, in other words, just turn
it on once instead of writing the MSR on every privilege level change.
When eIBRS is enabled, more privileged modes should be protected from
less privileged modes, including protecting VMMs from guests.
== Problem ==
Here's a simplification of how guests are run on Linux' KVM:
void run_kvm_guest(void)
{
// Prepare to run guest
VMRESUME();
// Clean up after guest runs
}
The execution flow for that would look something like this to the
processor:
1. Host-side: call run_kvm_guest()
2. Host-side: VMRESUME
3. Guest runs, does "CALL guest_function"
4. VM exit, host runs again
5. Host might make some "cleanup" function calls
6. Host-side: RET from run_kvm_guest()
Now, when back on the host, there are a couple of possible scenarios of
post-guest activity the host needs to do before executing host code:
* on pre-eIBRS hardware (legacy IBRS, or nothing at all), the RSB is not
touched and Linux has to do a 32-entry stuffing.
* on eIBRS hardware, VM exit with IBRS enabled, or restoring the host
IBRS=1 shortly after VM exit, has a documented side effect of flushing
the RSB except in this PBRSB situation where the software needs to stuff
the last RSB entry "by hand".
IOW, with eIBRS supported, host RET instructions should no longer be
influenced by guest behavior after the host retires a single CALL
instruction.
However, if the RET instructions are "unbalanced" with CALLs after a VM
exit as is the RET in #6, it might speculatively use the address for the
instruction after the CALL in #3 as an RSB prediction. This is a problem
since the (untrusted) guest controls this address.
Balanced CALL/RET instruction pairs such as in step #5 are not affected.
== Solution ==
The PBRSB issue affects a wide variety of Intel processors which
support eIBRS. But not all of them need mitigation. Today,
X86_FEATURE_RSB_VMEXIT triggers an RSB filling sequence that mitigates
PBRSB. Systems setting RSB_VMEXIT need no further mitigation - i.e.,
eIBRS systems which enable legacy IBRS explicitly.
However, such systems (X86_FEATURE_IBRS_ENHANCED) do not set RSB_VMEXIT
and most of them need a new mitigation.
Therefore, introduce a new feature flag X86_FEATURE_RSB_VMEXIT_LITE
which triggers a lighter-weight PBRSB mitigation versus RSB_VMEXIT.
The lighter-weight mitigation performs a CALL instruction which is
immediately followed by a speculative execution barrier (INT3). This
steers speculative execution to the barrier -- just like a retpoline
-- which ensures that speculation can never reach an unbalanced RET.
Then, ensure this CALL is retired before continuing execution with an
LFENCE.
In other words, the window of exposure is opened at VM exit where RET
behavior is troublesome. While the window is open, force RSB predictions
sampling for RET targets to a dead end at the INT3. Close the window
with the LFENCE.
There is a subset of eIBRS systems which are not vulnerable to PBRSB.
Add these systems to the cpu_vuln_whitelist[] as NO_EIBRS_PBRSB.
Future systems that aren't vulnerable will set ARCH_CAP_PBRSB_NO.
[ bp: Massage, incorporate review comments from Andy Cooper. ]
Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Co-developed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3ebc170068 upstream.
jmp2ret mitigates the easy-to-attack case at relatively low overhead.
It mitigates the long speculation windows after a mispredicted RET, but
it does not mitigate the short speculation window from arbitrary
instruction boundaries.
On Zen2, there is a chicken bit which needs setting, which mitigates
"arbitrary instruction boundaries" down to just "basic block boundaries".
But there is no fix for the short speculation window on basic block
boundaries, other than to flush the entire BTB to evict all attacker
predictions.
On the spectrum of "fast & blurry" -> "safe", there is (on top of STIBP
or no-SMT):
1) Nothing System wide open
2) jmp2ret May stop a script kiddy
3) jmp2ret+chickenbit Raises the bar rather further
4) IBPB Only thing which can count as "safe".
Tentative numbers put IBPB-on-entry at a 2.5x hit on Zen2, and a 10x hit
on Zen1 according to lmbench.
[ bp: Fixup feature bit comments, document option, 32-bit build fix. ]
Suggested-by: Andrew Cooper <Andrew.Cooper3@citrix.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7fbf47c7ce upstream.
Add the "retbleed=<value>" boot parameter to select a mitigation for
RETBleed. Possible values are "off", "auto" and "unret"
(JMP2RET mitigation). The default value is "auto".
Currently, "retbleed=auto" will select the unret mitigation on
AMD and Hygon and no mitigation on Intel (JMP2RET is not effective on
Intel).
[peterz: rebase; add hygon]
[jpoimboe: cleanups]
Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8cb861e9e3 upstream
Processor MMIO Stale Data is a class of vulnerabilities that may
expose data after an MMIO operation. For details please refer to
Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst.
These vulnerabilities are broadly categorized as:
Device Register Partial Write (DRPW):
Some endpoint MMIO registers incorrectly handle writes that are
smaller than the register size. Instead of aborting the write or only
copying the correct subset of bytes (for example, 2 bytes for a 2-byte
write), more bytes than specified by the write transaction may be
written to the register. On some processors, this may expose stale
data from the fill buffers of the core that created the write
transaction.
Shared Buffers Data Sampling (SBDS):
After propagators may have moved data around the uncore and copied
stale data into client core fill buffers, processors affected by MFBDS
can leak data from the fill buffer.
Shared Buffers Data Read (SBDR):
It is similar to Shared Buffer Data Sampling (SBDS) except that the
data is directly read into the architectural software-visible state.
An attacker can use these vulnerabilities to extract data from CPU fill
buffers using MDS and TAA methods. Mitigate it by clearing the CPU fill
buffers using the VERW instruction before returning to a user or a
guest.
On CPUs not affected by MDS and TAA, user application cannot sample data
from CPU fill buffers using MDS or TAA. A guest with MMIO access can
still use DRPW or SBDR to extract data architecturally. Mitigate it with
VERW instruction to clear fill buffers before VMENTER for MMIO capable
guests.
Add a kernel parameter mmio_stale_data={off|full|full,nosmt} to control
the mitigation.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 069c4ea687 upstream.
A semicolon was missing, and the almost-alphabetical-but-not ordering
was confusing, so regroup these by category instead.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d97c68d178 upstream.
If CONFIG_RANDOM_TRUST_CPU is set, the RNG initializes using RDRAND.
But, the user can disable (or enable) this behavior by setting
`random.trust_cpu=0/1` on the kernel command line. This allows system
builders to do reasonable things while avoiding howls from tinfoil
hatters. (Or vice versa.)
CONFIG_RANDOM_TRUST_BOOTLOADER is basically the same thing, but regards
the seed passed via EFI or device tree, which might come from RDRAND or
a TPM or somewhere else. In order to allow distros to more easily enable
this while avoiding those same howls (or vice versa), this commit adds
the corresponding `random.trust_bootloader=0/1` toggle.
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Graham Christensen <graham@grahamc.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Link: https://github.com/NixOS/nixpkgs/pull/165355
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 95e6060c20 upstream.
With tools like kbench9000 giving more finegrained responses, and this
basically never having been used ever since it was initially added,
let's just get rid of this. There *is* still work to be done on the
interrupt handler, but this really isn't the way it's being developed.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 489c7fc44b upstream.
Now that POOL_BITS == POOL_MIN_BITS, we must unconditionally wake up
entropy writers after every extraction. Therefore there's no point of
write_wakeup_threshold, so we can move it to the dustbin of unused
compatibility sysctls. While we're at it, we can fix a small comparison
where we were waking up after <= min rather than < min.
Cc: Theodore Ts'o <tytso@mit.edu>
Suggested-by: Eric Biggers <ebiggers@kernel.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 8484291132 ]
Although kptr_restrict is set to 0 and the kernel is booted with
no_hash_pointers parameter, the content of /proc/vmallocinfo is
lacking the real addresses.
/ # cat /proc/vmallocinfo
0x(ptrval)-0x(ptrval) 8192 load_module+0xc0c/0x2c0c pages=1 vmalloc
0x(ptrval)-0x(ptrval) 12288 start_kernel+0x4e0/0x690 pages=2 vmalloc
0x(ptrval)-0x(ptrval) 12288 start_kernel+0x4e0/0x690 pages=2 vmalloc
0x(ptrval)-0x(ptrval) 8192 _mpic_map_mmio.constprop.0+0x20/0x44 phys=0x80041000 ioremap
0x(ptrval)-0x(ptrval) 12288 _mpic_map_mmio.constprop.0+0x20/0x44 phys=0x80041000 ioremap
...
According to the documentation for /proc/sys/kernel/, %pK is
equivalent to %p when kptr_restrict is set to 0.
Fixes: 5ead723a20 ("lib/vsprintf: no_hash_pointers prints all addresses as unhashed")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/107476128e59bff11a309b5bf7579a1753a41aca.1645087605.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit e9b6013a7c upstream.
Update the link to the "Software Techniques for Managing Speculation
on AMD Processors" whitepaper.
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5ad3eb1132 upstream.
Update the doc with the new fun.
[ bp: Massage commit message. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
[fllinden@amazon.com: backported to 5.15]
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 82ca67321f upstream.
The config RANDOMIZE_SLAB does not exist, the authors probably intended to
refer to the config RANDOMIZE_BASE, which provides kernel address-space
randomization. They probably just confused SLAB with BASE (these two
four-letter words coincidentally share three common letters), as they also
point out the config SLAB_FREELIST_RANDOM as further randomization within
the same sentence.
Fix the reference of the config for kernel address-space randomization to
the config that provides that.
Fixes: 6e88559470 ("Documentation: Add section about CPU vulnerabilities for Spectre")
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Link: https://lore.kernel.org/r/20211230171940.27558-1-lukas.bulwahn@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9222ba68c3 ]
We've got a bug report about the non-working keyboard on ASUS ZenBook
UX425UA. It seems that the PS/2 device isn't ready immediately at
boot but takes some seconds to get ready. Until now, the only
workaround is to defer the probe, but it's available only when the
driver is a module. However, many distros, including openSUSE as in
the original report, build the PS/2 input drivers into kernel, hence
it won't work easily.
This patch adds the support for the deferred probe for i8042 stuff as
a workaround of the problem above. When the deferred probe mode is
enabled and the device couldn't be probed, it'll be repeated with the
standard deferred probe mechanism.
The deferred probe mode is enabled either via the new option
i8042.probe_defer or via the quirk table entry. As of this patch, the
quirk table contains only ASUS ZenBook UX425UA.
The deferred probe part is based on Fabio's initial work.
BugLink: https://bugzilla.suse.com/show_bug.cgi?id=1190256
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Samuel Čavoj <samuel@cavoj.net>
Link: https://lore.kernel.org/r/20211117063757.11380-1-tiwai@suse.de
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 0ff29701ff upstream.
Update the documentation for kvm-intel's emulate_invalid_guest_state to
rectify the description of KVM's default behavior, and to document that
the behavior and thus parameter only applies to L1.
Fixes: a27685c33a ("KVM: VMX: Emulate invalid guest state by default")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211207193006.120997-4-seanjc@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0f60a29c52 upstream.
The file name: accounting/delay-accounting.rst
should be, instead: Documentation/accounting/delay-accounting.rst.
Also, there's no need to use doc:`foo`, as automarkup.py will
automatically handle plain text mentions to Documentation/
files.
So, update its cross-reference accordingly.
Fixes: fcb5017045 ("delayacct: Document task_delayacct sysctl")
Fixes: c3123552aa ("docs: accounting: convert to ReST")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 40fdea0284 upstream.
When running as PVH or HVM guest with actual memory < max memory the
hypervisor is using "populate on demand" in order to allow the guest
to balloon down from its maximum memory size. For this to work
correctly the guest must not touch more memory pages than its target
memory size as otherwise the PoD cache will be exhausted and the guest
is crashed as a result of that.
In extreme cases ballooning down might not be finished today before
the init process is started, which can consume lots of memory.
In order to avoid random boot crashes in such cases, add a late init
call to wait for ballooning down having finished for PVH/HVM guests.
Warn on console if initial ballooning fails, panic() after stalling
for more than 3 minutes per default. Add a module parameter for
changing this timeout.
[boris: replaced pr_info() with pr_notice()]
Cc: <stable@vger.kernel.org>
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20211102091944.17487-1-jgross@suse.com
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull cgroup fixes from Tejun Heo:
"All documentation / comment updates"
* 'for-5.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroupv2, docs: fix misinformation in "device controller" section
cgroup/cpuset: Change references of cpuset_mutex to cpuset_rwsem
docs/cgroup: remove some duplicate words
Pull xen fixes from Juergen Gross:
- fix two minor issues in the Xen privcmd driver plus a cleanup patch
for that driver
- fix multiple issues related to running as PVH guest and some related
earlyprintk fixes for other Xen guest types
- fix an issue introduced in 5.15 the Xen balloon driver
* tag 'for-linus-5.15b-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/balloon: fix cancelled balloon action
xen/x86: adjust data placement
x86/PVH: adjust function/data placement
xen/x86: hook up xen_banner() also for PVH
xen/x86: generalize preferred console model from PV to PVH Dom0
xen/x86: make "earlyprintk=xen" work for HVM/PVH DomU
xen/x86: allow "earlyprintk=xen" to work for PV Dom0
xen/x86: make "earlyprintk=xen" work better for PVH Dom0
xen/x86: allow PVH Dom0 without XEN_PV=y
xen/x86: prevent PVH type from getting clobbered
xen/privcmd: drop "pages" parameter from xen_remap_pfn()
xen/privcmd: fix error handling in mmap-resource processing
xen/privcmd: replace kcalloc() by kvcalloc() when allocating empty pages
Hotmail was rejected by the mailing list, switched to gmail to resend.
1. Clarify cgroup BPF program type and attach type;
2. Fix file path broken.
Signed-off-by: ArthurChiao <arthurchiao@hotmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
When I tried to add some new entries to cgroup-v2.rst, I found that
the description of memory.events had some repetitive words, so I
tried to delete them.
Signed-off-by: Chunguang Xu <brookxu@tencent.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Merge patch series from Nick Desaulniers to update the minimum gcc
version to 5.1.
This is some of the left-overs from the merge window that I didn't want
to deal with yesterday, so it comes in after -rc1 but was sent before.
Gcc-4.9 support has been an annoyance for some time, and with -Werror I
had the choice of applying a fairly big patch from Kees Cook to remove a
fair number of initializer warnings (still leaving some), or this patch
series from Nick that just removes the source of the problem.
The initializer cleanups might still be worth it regardless, but
honestly, I preferred just tackling the problem with gcc-4.9 head-on.
We've been more aggressiuve about no longer having to care about
compilers that were released a long time ago, and I think it's been a
good thing.
I added a couple of patches on top to sort out a few left-overs now that
we no longer support gcc-4.x.
As noted by Arnd, as a result of this minimum compiler version upgrade
we can probably change our use of '--std=gnu89' to '--std=gnu11', and
finally start using local loop declarations etc. But this series does
_not_ yet do that.
Link: https://lore.kernel.org/all/20210909182525.372ee687@canb.auug.org.au/
Link: https://lore.kernel.org/lkml/CAK7LNASs6dvU6D3jL2GG3jW58fXfaj6VNOe55NJnTB8UPuk2pA@mail.gmail.com/
Link: https://github.com/ClangBuiltLinux/linux/issues/1438
* emailed patches from Nick Desaulniers <ndesaulniers@google.com>:
Drop some straggling mentions of gcc-4.9 as being stale
compiler_attributes.h: drop __has_attribute() support for gcc4
vmlinux.lds.h: remove old check for GCC 4.9
compiler-gcc.h: drop checks for older GCC versions
Makefile: drop GCC < 5 -fno-var-tracking-assignments workaround
arm64: remove GCC version check for ARCH_SUPPORTS_INT128
powerpc: remove GCC version check for UPD_CONSTR
riscv: remove Kconfig check for GCC version for ARCH_RV64I
Kconfig.debug: drop GCC 5+ version check for DWARF5
mm/ksm: remove old GCC 4.9+ check
compiler.h: drop fallback overflow checkers
Documentation: raise minimum supported version of GCC to 5.1
Fix up the admin-guide README file to the new gcc-5.1 requirement, and
remove a stale comment about gcc support for the __assume_aligned__
attribute.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull more tracing updates from Steven Rostedt:
- Add migrate-disable counter to tracing header
- Fix error handling in event probes
- Fix missed unlock in osnoise in error path
- Fix merge issue with tools/bootconfig
- Clean up bootconfig data when init memory is removed
- Fix bootconfig to loop only on subkeys
- Have kernel command lines override bootconfig options
- Increase field counts for synthetic events
- Have histograms dynamic allocate event elements to save space
- Fixes in testing and documentation
* tag 'trace-v5.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing/boot: Fix to loop on only subkeys
selftests/ftrace: Exclude "(fault)" in testing add/remove eprobe events
tracing: Dynamically allocate the per-elt hist_elt_data array
tracing: synth events: increase max fields count
tools/bootconfig: Show whole test command for each test case
bootconfig: Fix missing return check of xbc_node_compose_key function
tools/bootconfig: Fix tracing_on option checking in ftrace2bconf.sh
docs: bootconfig: Add how to use bootconfig for kernel parameters
init/bootconfig: Reorder init parameter from bootconfig and cmdline
init: bootconfig: Remove all bootconfig data when the init memory is removed
tracing/osnoise: Fix missed cpus_read_unlock() in start_per_cpu_kthreads()
tracing: Fix some alloc_event_probe() error handling bugs
tracing: Add migrate-disabled counter to tracing output.
Pull more ACPI updates from Rafael Wysocki:
"These add ACPI support to the PCI VMD driver, improve suspend-to-idle
support for AMD platforms and update documentation.
Specifics:
- Add ACPI support to the PCI VMD driver (Rafael Wysocki)
- Rearrange suspend-to-idle support code to reflect the platform
firmware expectations on some AMD platforms (Mario Limonciello)
- Make SSDT overlays documentation follow the code documented by it
more closely (Andy Shevchenko)"
* tag 'acpi-5.15-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: PM: s2idle: Run both AMD and Microsoft methods if both are supported
Documentation: ACPI: Align the SSDT overlays file with the code
PCI: VMD: ACPI: Make ACPI companion lookup work for VMD bus
Merge more updates from Andrew Morton:
"147 patches, based on 7d2a07b769.
Subsystems affected by this patch series: mm (memory-hotplug, rmap,
ioremap, highmem, cleanups, secretmem, kfence, damon, and vmscan),
alpha, percpu, procfs, misc, core-kernel, MAINTAINERS, lib,
checkpatch, epoll, init, nilfs2, coredump, fork, pids, criu, kconfig,
selftests, ipc, and scripts"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (94 commits)
scripts: check_extable: fix typo in user error message
mm/workingset: correct kernel-doc notations
ipc: replace costly bailout check in sysvipc_find_ipc()
selftests/memfd: remove unused variable
Kconfig.debug: drop selecting non-existing HARDLOCKUP_DETECTOR_ARCH
configs: remove the obsolete CONFIG_INPUT_POLLDEV
prctl: allow to setup brk for et_dyn executables
pid: cleanup the stale comment mentioning pidmap_init().
kernel/fork.c: unexport get_{mm,task}_exe_file
coredump: fix memleak in dump_vma_snapshot()
fs/coredump.c: log if a core dump is aborted due to changed file permissions
nilfs2: use refcount_dec_and_lock() to fix potential UAF
nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group
nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group
nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group
nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group
nilfs2: fix NULL pointer in nilfs_##name##_attr_release
nilfs2: fix memory leak in nilfs_sysfs_create_device_group
trap: cleanup trap_init()
init: move usermodehelper_enable() to populate_rootfs()
...
Pull iommu updates from Joerg Roedel:
- New DART IOMMU driver for Apple Silicon M1 chips
- Optimizations for iommu_[map/unmap] performance
- Selective TLB flush support for the AMD IOMMU driver to make it more
efficient on emulated IOMMUs
- Rework IOVA setup and default domain type setting to move more code
out of IOMMU drivers and to support runtime switching between certain
types of default domains
- VT-d Updates from Lu Baolu:
- Update the virtual command related registers
- Enable Intel IOMMU scalable mode by default
- Preset A/D bits for user space DMA usage
- Allow devices to have more than 32 outstanding PRs
- Various cleanups
- ARM SMMU Updates from Will Deacon:
SMMUv3:
- Minor optimisation to avoid zeroing struct members on CMD submission
- Increased use of batched commands to reduce submission latency
- Refactoring in preparation for ECMDQ support
SMMUv2:
- Fix races when probing devices with identical StreamIDs
- Optimise walk cache flushing for Qualcomm implementations
- Allow deep sleep states for some Qualcomm SoCs with shared clocks
- Various smaller optimizations, cleanups, and fixes
* tag 'iommu-updates-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (85 commits)
iommu/io-pgtable: Abstract iommu_iotlb_gather access
iommu/arm-smmu: Fix missing unlock on error in arm_smmu_device_group()
iommu/vt-d: Add present bit check in pasid entry setup helpers
iommu/vt-d: Use pasid_pte_is_present() helper function
iommu/vt-d: Drop the kernel doc annotation
iommu/vt-d: Allow devices to have more than 32 outstanding PRs
iommu/vt-d: Preset A/D bits for user space DMA usage
iommu/vt-d: Enable Intel IOMMU scalable mode by default
iommu/vt-d: Refactor Kconfig a bit
iommu/vt-d: Remove unnecessary oom message
iommu/vt-d: Update the virtual command related registers
iommu: Allow enabling non-strict mode dynamically
iommu: Merge strictness and domain type configs
iommu: Only log strictness for DMA domains
iommu: Expose DMA domain strictness via sysfs
iommu: Express DMA strictness via the domain type
iommu/vt-d: Prepare for multiple DMA domain types
iommu/arm-smmu: Prepare for multiple DMA domain types
iommu/amd: Prepare for multiple DMA domain types
iommu: Introduce explicit type for non-strict DMA domains
...
Merge misc updates from Andrew Morton:
"173 patches.
Subsystems affected by this series: ia64, ocfs2, block, and mm (debug,
pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure,
hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock,
oom-kill, migration, ksm, percpu, vmstat, and madvise)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits)
mm/madvise: add MADV_WILLNEED to process_madvise()
mm/vmstat: remove unneeded return value
mm/vmstat: simplify the array size calculation
mm/vmstat: correct some wrong comments
mm/percpu,c: remove obsolete comments of pcpu_chunk_populated()
selftests: vm: add COW time test for KSM pages
selftests: vm: add KSM merging time test
mm: KSM: fix data type
selftests: vm: add KSM merging across nodes test
selftests: vm: add KSM zero page merging test
selftests: vm: add KSM unmerge test
selftests: vm: add KSM merge test
mm/migrate: correct kernel-doc notation
mm: wire up syscall process_mrelease
mm: introduce process_mrelease system call
memblock: make memblock_find_in_range method private
mm/mempolicy.c: use in_task() in mempolicy_slab_node()
mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies
mm/mempolicy: advertise new MPOL_PREFERRED_MANY
mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY
...
The proactive compaction[1] gets triggered for every 500msec and run
compaction on the node for COMPACTION_HPAGE_ORDER (usually order-9) pages
based on the value set to sysctl.compaction_proactiveness. Triggering the
compaction for every 500msec in search of COMPACTION_HPAGE_ORDER pages is
not needed for all applications, especially on the embedded system
usecases which may have few MB's of RAM. Enabling the proactive
compaction in its state will endup in running almost always on such
systems.
Other side, proactive compaction can still be very much useful for getting
a set of higher order pages in some controllable manner(controlled by
using the sysctl.compaction_proactiveness). So, on systems where enabling
the proactive compaction always may proove not required, can trigger the
same from user space on write to its sysctl interface. As an example, say
app launcher decide to launch the memory heavy application which can be
launched fast if it gets more higher order pages thus launcher can prepare
the system in advance by triggering the proactive compaction from
userspace.
This triggering of proactive compaction is done on a write to
sysctl.compaction_proactiveness by user.
[1]https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=facdaa917c4d5a376d09d25865f5a863f906234a
[akpm@linux-foundation.org: tweak vm.rst, per Mike]
Link: https://lkml.kernel.org/r/1627653207-12317-1-git-send-email-charante@codeaurora.org
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Rafael Aquini <aquini@redhat.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Nitin Gupta <nigupta@nvidia.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull rdma updates from Jason Gunthorpe:
"This is quite a small cycle, no major series stands out. The HNS and
rxe drivers saw the most activity this cycle, with rxe being broken
for a good chunk of time. The significant deleted line count is due to
a SPDX cleanup series.
Summary:
- Various cleanup and small features for rtrs
- kmap_local_page() conversions
- Driver updates and fixes for: efa, rxe, mlx5, hfi1, qed, hns
- Cache the IB subnet prefix
- Rework how CRC is calcuated in rxe
- Clean reference counting in iwpm's netlink
- Pull object allocation and lifecycle for user QPs to the uverbs
core code
- Several small hns features and continued general code cleanups
- Fix the scatterlist confusion of orig_nents/nents introduced in an
earlier patch creating the append operation"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (90 commits)
RDMA/mlx5: Relax DCS QP creation checks
RDMA/hns: Delete unnecessary blank lines.
RDMA/hns: Encapsulate the qp db as a function
RDMA/hns: Adjust the order in which irq are requested and enabled
RDMA/hns: Remove RST2RST error prints for hw v1
RDMA/hns: Remove dqpn filling when modify qp from Init to Init
RDMA/hns: Fix QP's resp incomplete assignment
RDMA/hns: Fix query destination qpn
RDMA/hfi1: Convert to SPDX identifier
IB/rdmavt: Convert to SPDX identifier
RDMA/hns: Bugfix for incorrect association between dip_idx and dgid
RDMA/hns: Bugfix for the missing assignment for dip_idx
RDMA/hns: Bugfix for data type of dip_idx
RDMA/hns: Fix incorrect lsn field
RDMA/irdma: Remove the repeated declaration
RDMA/core/sa_query: Retry SA queries
RDMA: Use the sg_table directly and remove the opencoded version from umem
lib/scatterlist: Fix wrong update of orig_nents
lib/scatterlist: Provide a dedicated function to support table append
RDMA/hns: Delete unused hns bitmap interface
...
