Commit Graph

616 Commits

Author SHA1 Message Date
Kim Phillips
6b21077146 iommu/amd: Fix ill-formed ivrs_ioapic, ivrs_hpet and ivrs_acpihid options
[ Upstream commit 1198d2316dc4265a97d0e8445a22c7a6d17580a4 ]

Currently, these options cause the following libkmod error:

libkmod: ERROR ../libkmod/libkmod-config.c:489 kcmdline_parse_result: \
	Ignoring bad option on kernel command line while parsing module \
	name: 'ivrs_xxxx[XX:XX'

Fix by introducing a new parameter format for these options and
throw a warning for the deprecated format.

Users are still allowed to omit the PCI Segment if zero.

Adding a Link: to the reason why we're modding the syntax parsing
in the driver and not in libkmod.

Fixes: ca3bf5d47c ("iommu/amd: Introduces ivrs_acpihid kernel parameter")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/linux-modules/20200310082308.14318-2-lucas.demarchi@intel.com/
Reported-by: Kim Phillips <kim.phillips@amd.com>
Co-developed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Link: https://lore.kernel.org/r/20220919155638.391481-2-kim.phillips@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18 11:44:55 +01:00
Suravee Suthikulpanit
5badda810f iommu/amd: Add PCI segment support for ivrs_[ioapic/hpet/acpihid] commands
[ Upstream commit bbe3a106580c21bc883fb0c9fa3da01534392fe8 ]

By default, PCI segment is zero and can be omitted. To support system
with non-zero PCI segment ID, modify the parsing functions to allow
PCI segment ID.

Co-developed-by: Vasant Hegde <vasant.hegde@amd.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20220706113825.25582-33-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Stable-dep-of: 1198d2316dc4 ("iommu/amd: Fix ill-formed ivrs_ioapic, ivrs_hpet and ivrs_acpihid options")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18 11:44:55 +01:00
Kim Phillips
fd96b61389 x86/bugs: Enable STIBP for IBPB mitigated RETBleed
commit e6cfcdda8cbe81eaf821c897369a65fec987b404 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: 3ebc17006888 ("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>
2022-08-21 15:16:14 +02:00
Eiichi Tsukata
aadc39fd5b docs/kernel-parameters: Update descriptions for "mitigations=" param with retbleed
commit ea304a8b89fd0d6cf94ee30cb139dc23d9f1a62f upstream.

Updates descriptions for "mitigations=off" and "mitigations=auto,nosmt"
with the respective retbleed= settings.

Signed-off-by: Eiichi Tsukata <eiichi.tsukata@nutanix.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: corbet@lwn.net
Link: https://lore.kernel.org/r/20220728043907.165688-1-eiichi.tsukata@nutanix.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-03 12:00:50 +02:00
Peter Zijlstra
c8845b8754 x86/bugs: Add retbleed=ibpb
commit 3ebc170068885b6fc7bedda6c667bb2c4d533159 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>
[bwh: Backported to 5.10: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:44 +02:00
Pawan Gupta
dabc2a1b40 x86/speculation: Add spectre_v2=ibrs option to support Kernel IBRS
commit 7c693f54c873691a4b7da05c7e0f74e67745d144 upstream.

Extend spectre_v2= boot option with Kernel IBRS.

  [jpoimboe: no STIBP with IBRS]

Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.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: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:42 +02:00
Kim Phillips
a989e75136 x86/bugs: Enable STIBP for JMP2RET
commit e8ec1b6e08a2102d8755ccb06fa26d540f26a2fa upstream.

For untrained return thunks to be fully effective, STIBP must be enabled
or SMT disabled.

Co-developed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:41 +02:00
Alexandre Chartre
3f29791d56 x86/bugs: Add AMD retbleed= boot parameter
commit 7fbf47c7ce50b38a64576b150e7011ae73d54669 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: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:40 +02:00
Pawan Gupta
26f6f231f6 x86/speculation/mmio: Add mitigation for Processor MMIO Stale Data
commit 8cb861e9e3c9a55099ad3d08e1a3b653d29c33ca 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>
2022-06-16 13:27:58 +02:00
Jason A. Donenfeld
f3bc5eca83 random: treat bootloader trust toggle the same way as cpu trust toggle
commit d97c68d178fbf8aaaf21b69b446f2dfb13909316 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>
2022-05-30 09:33:38 +02:00
Peter Zijlstra
071e8b69d7 Documentation/hw-vuln: Update spectre doc
commit 5ad3eb1132453b9795ce5fd4572b1c18b292cca9 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 5.10]
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-11 12:11:49 +01:00
Takashi Iwai
bb672eff74 Input: i8042 - add deferred probe support
[ Upstream commit 9222ba68c3f4065f6364b99cc641b6b019ef2d42 ]

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>
2022-01-05 12:40:29 +01:00
Sean Christopherson
8008fc1d0b KVM: VMX: Fix stale docs for kvm-intel.emulate_invalid_guest_state
commit 0ff29701ffad9a5d5a24344d8b09f3af7b96ffda 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>
2021-12-29 12:26:05 +01:00
Juergen Gross
af7d25d785 xen/balloon: add late_initcall_sync() for initial ballooning done
commit 40fdea0284bb20814399da0484a658a96c735d90 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>
2021-11-18 14:03:49 +01:00
Paul E. McKenney
03a65c14ab clocksource: Retry clock read if long delays detected
[ Upstream commit db3a34e17433de2390eb80d436970edcebd0ca3e ]

When the clocksource watchdog marks a clock as unstable, this might be due
to that clock being unstable or it might be due to delays that happen to
occur between the reads of the two clocks.  Yes, interrupts are disabled
across those two reads, but there are no shortage of things that can delay
interrupts-disabled regions of code ranging from SMI handlers to vCPU
preemption.  It would be good to have some indication as to why the clock
was marked unstable.

Therefore, re-read the watchdog clock on either side of the read from the
clock under test.  If the watchdog clock shows an excessive time delta
between its pair of reads, the reads are retried.

The maximum number of retries is specified by a new kernel boot parameter
clocksource.max_cswd_read_retries, which defaults to three, that is, up to
four reads, one initial and up to three retries.  If more than one retry
was required, a message is printed on the console (the occasional single
retry is expected behavior, especially in guest OSes).  If the maximum
number of retries is exceeded, the clock under test will be marked
unstable.  However, the probability of this happening due to various sorts
of delays is quite small.  In addition, the reason (clock-read delays) for
the unstable marking will be apparent.

Reported-by: Chris Mason <clm@fb.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Feng Tang <feng.tang@intel.com>
Link: https://lore.kernel.org/r/20210527190124.440372-1-paulmck@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14 16:56:01 +02:00
David Woodhouse
a8fddd4192 x86/xen: Add xen_no_vector_callback option to test PCI INTX delivery
[ Upstream commit b36b0fe96af13460278bf9b173beced1bd15f85d ]

It's useful to be able to test non-vector event channel delivery, to make
sure Linux will work properly on older Xen which doesn't have it.

It's also useful for those working on Xen and Xen-compatible hypervisors,
because there are guest kernels still in active use which use PCI INTX
even when vector delivery is available.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20210106153958.584169-4-dwmw2@infradead.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-27 11:55:01 +01:00
Oliver Neukum
2440c1cb25 USB: UAS: introduce a quirk to set no_write_same
commit 8010622c86ca5bb44bc98492f5968726fc7c7a21 upstream.

UAS does not share the pessimistic assumption storage is making that
devices cannot deal with WRITE_SAME.  A few devices supported by UAS,
are reported to not deal well with WRITE_SAME. Those need a quirk.

Add it to the device that needs it.

Reported-by: David C. Partridge <david.partridge@perdrix.co.uk>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201209152639.9195-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-21 13:30:08 +01:00
Nicholas Piggin
9a32a7e78b powerpc/64s: flush L1D after user accesses
IBM Power9 processors can speculatively operate on data in the L1 cache
before it has been completely validated, via a way-prediction mechanism. It
is not possible for an attacker to determine the contents of impermissible
memory using this method, since these systems implement a combination of
hardware and software security measures to prevent scenarios where
protected data could be leaked.

However these measures don't address the scenario where an attacker induces
the operating system to speculatively execute instructions using data that
the attacker controls. This can be used for example to speculatively bypass
"kernel user access prevention" techniques, as discovered by Anthony
Steinhauser of Google's Safeside Project. This is not an attack by itself,
but there is a possibility it could be used in conjunction with
side-channels or other weaknesses in the privileged code to construct an
attack.

This issue can be mitigated by flushing the L1 cache between privilege
boundaries of concern. This patch flushes the L1 cache after user accesses.

This is part of the fix for CVE-2020-4788.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2020-11-19 23:47:18 +11:00
Nicholas Piggin
f79643787e powerpc/64s: flush L1D on kernel entry
IBM Power9 processors can speculatively operate on data in the L1 cache
before it has been completely validated, via a way-prediction mechanism. It
is not possible for an attacker to determine the contents of impermissible
memory using this method, since these systems implement a combination of
hardware and software security measures to prevent scenarios where
protected data could be leaked.

However these measures don't address the scenario where an attacker induces
the operating system to speculatively execute instructions using data that
the attacker controls. This can be used for example to speculatively bypass
"kernel user access prevention" techniques, as discovered by Anthony
Steinhauser of Google's Safeside Project. This is not an attack by itself,
but there is a possibility it could be used in conjunction with
side-channels or other weaknesses in the privileged code to construct an
attack.

This issue can be mitigated by flushing the L1 cache between privilege
boundaries of concern. This patch flushes the L1 cache on kernel entry.

This is part of the fix for CVE-2020-4788.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2020-11-19 23:47:15 +11:00
Linus Torvalds
bd6aabc7ca Merge tag 'for-linus-5.10b-rc1c-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull more xen updates from Juergen Gross:

 - a series for the Xen pv block drivers adding module parameters for
   better control of resource usge

 - a cleanup series for the Xen event driver

* tag 'for-linus-5.10b-rc1c-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  Documentation: add xen.fifo_events kernel parameter description
  xen/events: unmask a fifo event channel only if it was masked
  xen/events: only register debug interrupt for 2-level events
  xen/events: make struct irq_info private to events_base.c
  xen: remove no longer used functions
  xen-blkfront: Apply changed parameter name to the document
  xen-blkfront: add a parameter for disabling of persistent grants
  xen-blkback: add a parameter for disabling of persistent grants
2020-10-25 10:55:35 -07:00
Juergen Gross
1a89c1dc95 Documentation: add xen.fifo_events kernel parameter description
The kernel boot parameter xen.fifo_events isn't listed in
Documentation/admin-guide/kernel-parameters.txt. Add it.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Link: https://lore.kernel.org/r/20201022094907.28560-6-jgross@suse.com
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-10-23 05:41:25 -05:00
Linus Torvalds
4a5bb973fa Merge tag 'for-linus-5.10b-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull more xen updates from Juergen Gross:

 - A single patch to fix the Xen security issue XSA-331 (malicious
   guests can DoS dom0 by triggering NULL-pointer dereferences or access
   to stale data).

 - A larger series to fix the Xen security issue XSA-332 (malicious
   guests can DoS dom0 by sending events at high frequency leading to
   dom0's vcpus being busy in IRQ handling for elongated times).

* tag 'for-linus-5.10b-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/events: block rogue events for some time
  xen/events: defer eoi in case of excessive number of events
  xen/events: use a common cpu hotplug hook for event channels
  xen/events: switch user event channels to lateeoi model
  xen/pciback: use lateeoi irq binding
  xen/pvcallsback: use lateeoi irq binding
  xen/scsiback: use lateeoi irq binding
  xen/netback: use lateeoi irq binding
  xen/blkback: use lateeoi irq binding
  xen/events: add a new "late EOI" evtchn framework
  xen/events: fix race in evtchn_fifo_unmask()
  xen/events: add a proper barrier to 2-level uevent unmasking
  xen/events: avoid removing an event channel while handling it
2020-10-20 09:24:01 -07:00
Juergen Gross
e99502f762 xen/events: defer eoi in case of excessive number of events
In case rogue guests are sending events at high frequency it might
happen that xen_evtchn_do_upcall() won't stop processing events in
dom0. As this is done in irq handling a crash might be the result.

In order to avoid that, delay further inter-domain events after some
time in xen_evtchn_do_upcall() by forcing eoi processing into a
worker on the same cpu, thus inhibiting new events coming in.

The time after which eoi processing is to be delayed is configurable
via a new module parameter "event_loop_timeout" which specifies the
maximum event loop time in jiffies (default: 2, the value was chosen
after some tests showing that a value of 2 was the lowest with an
only slight drop of dom0 network throughput while multiple guests
performed an event storm).

How long eoi processing will be delayed can be specified via another
parameter "event_eoi_delay" (again in jiffies, default 10, again the
value was chosen after testing with different delay values).

This is part of XSA-332.

Cc: stable@vger.kernel.org
Reported-by: Julien Grall <julien@xen.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Wei Liu <wl@xen.org>
2020-10-20 10:22:16 +02:00
Linus Torvalds
41eea65e2a Merge tag 'core-rcu-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU changes from Ingo Molnar:

 - Debugging for smp_call_function()

 - RT raw/non-raw lock ordering fixes

 - Strict grace periods for KASAN

 - New smp_call_function() torture test

 - Torture-test updates

 - Documentation updates

 - Miscellaneous fixes

[ This doesn't actually pull the tag - I've dropped the last merge from
  the RCU branch due to questions about the series.   - Linus ]

* tag 'core-rcu-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (77 commits)
  smp: Make symbol 'csd_bug_count' static
  kernel/smp: Provide CSD lock timeout diagnostics
  smp: Add source and destination CPUs to __call_single_data
  rcu: Shrink each possible cpu krcp
  rcu/segcblist: Prevent useless GP start if no CBs to accelerate
  torture: Add gdb support
  rcutorture: Allow pointer leaks to test diagnostic code
  rcutorture: Hoist OOM registry up one level
  refperf: Avoid null pointer dereference when buf fails to allocate
  rcutorture: Properly synchronize with OOM notifier
  rcutorture: Properly set rcu_fwds for OOM handling
  torture: Add kvm.sh --help and update help message
  rcutorture: Add CONFIG_PROVE_RCU_LIST to TREE05
  torture: Update initrd documentation
  rcutorture: Replace HTTP links with HTTPS ones
  locktorture: Make function torture_percpu_rwsem_init() static
  torture: document --allcpus argument added to the kvm.sh script
  rcutorture: Output number of elapsed grace periods
  rcutorture: Remove KCSAN stubs
  rcu: Remove unused "cpu" parameter from rcu_report_qs_rdp()
  ...
2020-10-18 14:34:50 -07:00
Linus Torvalds
c4cf498dc0 Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:
 "155 patches.

  Subsystems affected by this patch series: mm (dax, debug, thp,
  readahead, page-poison, util, memory-hotplug, zram, cleanups), misc,
  core-kernel, get_maintainer, MAINTAINERS, lib, bitops, checkpatch,
  binfmt, ramfs, autofs, nilfs, rapidio, panic, relay, kgdb, ubsan,
  romfs, and fault-injection"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (155 commits)
  lib, uaccess: add failure injection to usercopy functions
  lib, include/linux: add usercopy failure capability
  ROMFS: support inode blocks calculation
  ubsan: introduce CONFIG_UBSAN_LOCAL_BOUNDS for Clang
  sched.h: drop in_ubsan field when UBSAN is in trap mode
  scripts/gdb/tasks: add headers and improve spacing format
  scripts/gdb/proc: add struct mount & struct super_block addr in lx-mounts command
  kernel/relay.c: drop unneeded initialization
  panic: dump registers on panic_on_warn
  rapidio: fix the missed put_device() for rio_mport_add_riodev
  rapidio: fix error handling path
  nilfs2: fix some kernel-doc warnings for nilfs2
  autofs: harden ioctl table
  ramfs: fix nommu mmap with gaps in the page cache
  mm: remove the now-unnecessary mmget_still_valid() hack
  mm/gup: take mmap_lock in get_dump_page()
  binfmt_elf, binfmt_elf_fdpic: use a VMA list snapshot
  coredump: rework elf/elf_fdpic vma_dump_size() into common helper
  coredump: refactor page range dumping into common helper
  coredump: let dump_emit() bail out on short writes
  ...
2020-10-16 11:31:55 -07:00
Albert van der Linde
2c739ced58 lib, include/linux: add usercopy failure capability
Patch series "add fault injection to user memory access", v3.

The goal of this series is to improve testing of fault-tolerance in usages
of user memory access functions, by adding support for fault injection.

syzkaller/syzbot are using the existing fault injection modes and will use
this particular feature also.

The first patch adds failure injection capability for usercopy functions.
The second changes usercopy functions to use this new failure capability
(copy_from_user, ...).  The third patch adds get/put/clear_user failures
to x86.

This patch (of 3):

Add a failure injection capability to improve testing of fault-tolerance
in usages of user memory access functions.

Add CONFIG_FAULT_INJECTION_USERCOPY to enable faults in usercopy
functions.  The should_fail_usercopy function is to be called by these
functions (copy_from_user, get_user, ...) in order to fail or not.

Signed-off-by: Albert van der Linde <alinde@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/20200831171733.955393-1-alinde@google.com
Link: http://lkml.kernel.org/r/20200831171733.955393-2-alinde@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16 11:11:22 -07:00
Linus Torvalds
9ff9b0d392 Merge tag 'net-next-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Jakub Kicinski:

 - Add redirect_neigh() BPF packet redirect helper, allowing to limit
   stack traversal in common container configs and improving TCP
   back-pressure.

   Daniel reports ~10Gbps => ~15Gbps single stream TCP performance gain.

 - Expand netlink policy support and improve policy export to user
   space. (Ge)netlink core performs request validation according to
   declared policies. Expand the expressiveness of those policies
   (min/max length and bitmasks). Allow dumping policies for particular
   commands. This is used for feature discovery by user space (instead
   of kernel version parsing or trial and error).

 - Support IGMPv3/MLDv2 multicast listener discovery protocols in
   bridge.

 - Allow more than 255 IPv4 multicast interfaces.

 - Add support for Type of Service (ToS) reflection in SYN/SYN-ACK
   packets of TCPv6.

 - In Multi-patch TCP (MPTCP) support concurrent transmission of data on
   multiple subflows in a load balancing scenario. Enhance advertising
   addresses via the RM_ADDR/ADD_ADDR options.

 - Support SMC-Dv2 version of SMC, which enables multi-subnet
   deployments.

 - Allow more calls to same peer in RxRPC.

 - Support two new Controller Area Network (CAN) protocols - CAN-FD and
   ISO 15765-2:2016.

 - Add xfrm/IPsec compat layer, solving the 32bit user space on 64bit
   kernel problem.

 - Add TC actions for implementing MPLS L2 VPNs.

 - Improve nexthop code - e.g. handle various corner cases when nexthop
   objects are removed from groups better, skip unnecessary
   notifications and make it easier to offload nexthops into HW by
   converting to a blocking notifier.

 - Support adding and consuming TCP header options by BPF programs,
   opening the doors for easy experimental and deployment-specific TCP
   option use.

 - Reorganize TCP congestion control (CC) initialization to simplify
   life of TCP CC implemented in BPF.

 - Add support for shipping BPF programs with the kernel and loading
   them early on boot via the User Mode Driver mechanism, hence reusing
   all the user space infra we have.

 - Support sleepable BPF programs, initially targeting LSM and tracing.

 - Add bpf_d_path() helper for returning full path for given 'struct
   path'.

 - Make bpf_tail_call compatible with bpf-to-bpf calls.

 - Allow BPF programs to call map_update_elem on sockmaps.

 - Add BPF Type Format (BTF) support for type and enum discovery, as
   well as support for using BTF within the kernel itself (current use
   is for pretty printing structures).

 - Support listing and getting information about bpf_links via the bpf
   syscall.

 - Enhance kernel interfaces around NIC firmware update. Allow
   specifying overwrite mask to control if settings etc. are reset
   during update; report expected max time operation may take to users;
   support firmware activation without machine reboot incl. limits of
   how much impact reset may have (e.g. dropping link or not).

 - Extend ethtool configuration interface to report IEEE-standard
   counters, to limit the need for per-vendor logic in user space.

 - Adopt or extend devlink use for debug, monitoring, fw update in many
   drivers (dsa loop, ice, ionic, sja1105, qed, mlxsw, mv88e6xxx,
   dpaa2-eth).

 - In mlxsw expose critical and emergency SFP module temperature alarms.
   Refactor port buffer handling to make the defaults more suitable and
   support setting these values explicitly via the DCBNL interface.

 - Add XDP support for Intel's igb driver.

 - Support offloading TC flower classification and filtering rules to
   mscc_ocelot switches.

 - Add PTP support for Marvell Octeontx2 and PP2.2 hardware, as well as
   fixed interval period pulse generator and one-step timestamping in
   dpaa-eth.

 - Add support for various auth offloads in WiFi APs, e.g. SAE (WPA3)
   offload.

 - Add Lynx PHY/PCS MDIO module, and convert various drivers which have
   this HW to use it. Convert mvpp2 to split PCS.

 - Support Marvell Prestera 98DX3255 24-port switch ASICs, as well as
   7-port Mediatek MT7531 IP.

 - Add initial support for QCA6390 and IPQ6018 in ath11k WiFi driver,
   and wcn3680 support in wcn36xx.

 - Improve performance for packets which don't require much offloads on
   recent Mellanox NICs by 20% by making multiple packets share a
   descriptor entry.

 - Move chelsio inline crypto drivers (for TLS and IPsec) from the
   crypto subtree to drivers/net. Move MDIO drivers out of the phy
   directory.

 - Clean up a lot of W=1 warnings, reportedly the actively developed
   subsections of networking drivers should now build W=1 warning free.

 - Make sure drivers don't use in_interrupt() to dynamically adapt their
   code. Convert tasklets to use new tasklet_setup API (sadly this
   conversion is not yet complete).

* tag 'net-next-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2583 commits)
  Revert "bpfilter: Fix build error with CONFIG_BPFILTER_UMH"
  net, sockmap: Don't call bpf_prog_put() on NULL pointer
  bpf, selftest: Fix flaky tcp_hdr_options test when adding addr to lo
  bpf, sockmap: Add locking annotations to iterator
  netfilter: nftables: allow re-computing sctp CRC-32C in 'payload' statements
  net: fix pos incrementment in ipv6_route_seq_next
  net/smc: fix invalid return code in smcd_new_buf_create()
  net/smc: fix valid DMBE buffer sizes
  net/smc: fix use-after-free of delayed events
  bpfilter: Fix build error with CONFIG_BPFILTER_UMH
  cxgb4/ch_ipsec: Replace the module name to ch_ipsec from chcr
  net: sched: Fix suspicious RCU usage while accessing tcf_tunnel_info
  bpf: Fix register equivalence tracking.
  rxrpc: Fix loss of final ack on shutdown
  rxrpc: Fix bundle counting for exclusive connections
  netfilter: restore NF_INET_NUMHOOKS
  ibmveth: Identify ingress large send packets.
  ibmveth: Switch order of ibmveth_helper calls.
  cxgb4: handle 4-tuple PEDIT to NAT mode translation
  selftests: Add VRF route leaking tests
  ...
2020-10-15 18:42:13 -07:00
Linus Torvalds
5a32c3413d Merge tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:

 - rework the non-coherent DMA allocator

 - move private definitions out of <linux/dma-mapping.h>

 - lower CMA_ALIGNMENT (Paul Cercueil)

 - remove the omap1 dma address translation in favor of the common code

 - make dma-direct aware of multiple dma offset ranges (Jim Quinlan)

 - support per-node DMA CMA areas (Barry Song)

 - increase the default seg boundary limit (Nicolin Chen)

 - misc fixes (Robin Murphy, Thomas Tai, Xu Wang)

 - various cleanups

* tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mapping: (63 commits)
  ARM/ixp4xx: add a missing include of dma-map-ops.h
  dma-direct: simplify the DMA_ATTR_NO_KERNEL_MAPPING handling
  dma-direct: factor out a dma_direct_alloc_from_pool helper
  dma-direct check for highmem pages in dma_direct_alloc_pages
  dma-mapping: merge <linux/dma-noncoherent.h> into <linux/dma-map-ops.h>
  dma-mapping: move large parts of <linux/dma-direct.h> to kernel/dma
  dma-mapping: move dma-debug.h to kernel/dma/
  dma-mapping: remove <asm/dma-contiguous.h>
  dma-mapping: merge <linux/dma-contiguous.h> into <linux/dma-map-ops.h>
  dma-contiguous: remove dma_contiguous_set_default
  dma-contiguous: remove dev_set_cma_area
  dma-contiguous: remove dma_declare_contiguous
  dma-mapping: split <linux/dma-mapping.h>
  cma: decrease CMA_ALIGNMENT lower limit to 2
  firewire-ohci: use dma_alloc_pages
  dma-iommu: implement ->alloc_noncoherent
  dma-mapping: add new {alloc,free}_noncoherent dma_map_ops methods
  dma-mapping: add a new dma_alloc_pages API
  dma-mapping: remove dma_cache_sync
  53c700: convert to dma_alloc_noncoherent
  ...
2020-10-15 14:43:29 -07:00
Linus Torvalds
50d228345a Merge tag 'docs-5.10' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
 "As hoped, things calmed down for docs this cycle; fewer changes and
  almost no conflicts at all. This includes:

   - A reworked and expanded user-mode Linux document

   - Some simplifications and improvements for submitting-patches.rst

   - An emergency fix for (some) problems with Sphinx 3.x

   - Some welcome automarkup improvements to automatically generate
     cross-references to struct definitions and other documents

   - The usual collection of translation updates, typo fixes, etc"

* tag 'docs-5.10' of git://git.lwn.net/linux: (81 commits)
  gpiolib: Update indentation in driver.rst for code excerpts
  Documentation/admin-guide: tainted-kernels: Fix typo occured
  Documentation: better locations for sysfs-pci, sysfs-tagging
  docs: programming-languages: refresh blurb on clang support
  Documentation: kvm: fix a typo
  Documentation: Chinese translation of Documentation/arm64/amu.rst
  doc: zh_CN: index files in arm64 subdirectory
  mailmap: add entry for <mstarovoitov@marvell.com>
  doc: seq_file: clarify role of *pos in ->next()
  docs: trace: ring-buffer-design.rst: use the new SPDX tag
  Documentation: kernel-parameters: clarify "module." parameters
  Fix references to nommu-mmap.rst
  docs: rewrite admin-guide/sysctl/abi.rst
  docs: fb: Remove vesafb scrollback boot option
  docs: fb: Remove sstfb scrollback boot option
  docs: fb: Remove matroxfb scrollback boot option
  docs: fb: Remove framebuffer scrollback boot option
  docs: replace the old User Mode Linux HowTo with a new one
  Documentation/admin-guide: blockdev/ramdisk: remove use of "rdev"
  Documentation/admin-guide: README & svga: remove use of "rdev"
  ...
2020-10-12 16:21:29 -07:00
Ingo Molnar
b36c830f8c Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull v5.10 RCU changes from Paul E. McKenney:

- Debugging for smp_call_function().

- Strict grace periods for KASAN.  The point of this series is to find
  RCU-usage bugs, so the corresponding new RCU_STRICT_GRACE_PERIOD
  Kconfig option depends on both DEBUG_KERNEL and RCU_EXPERT, and is
  further disabled by dfefault.  Finally, the help text includes
  a goodly list of scary caveats.

- New smp_call_function() torture test.

- Torture-test updates.

- Documentation updates.

- Miscellaneous fixes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-10-09 08:21:56 +02:00
Christoph Hellwig
0b1abd1fb7 dma-mapping: merge <linux/dma-contiguous.h> into <linux/dma-map-ops.h>
Merge dma-contiguous.h into dma-map-ops.h, after removing the comment
describing the contiguous allocator into kernel/dma/contigous.c.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:04 +02:00
Randy Dunlap
307e3ee934 Documentation: kernel-parameters: clarify "module." parameters
The command-line parameters "dyndbg" and "async_probe" are not
parameters for kernel/module.c but instead they are for the
module that is being loaded. Try to make that distinction in the
help text.

OTOH, "module.sig_enforce" is handled as a parameter of kernel/module.c
so "module." is correct for it.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Link: https://lore.kernel.org/r/67d40b6d-c073-a3bf-cbb6-6cad941cceeb@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24 11:06:05 -06:00
Randy Dunlap
6b99e6e6aa Documentation/admin-guide: blockdev/ramdisk: remove use of "rdev"
Remove use of "rdev" from blockdev/ramdisk.rst and update
admin-guide/kernel-parameters.txt.

"rdev" is considered antiquated, ancient, archaic, obsolete, deprecated
{choose any or all}.

"rdev" was removed from util-linux in 2010:
  https://git.kernel.org/pub/scm/utils/util-linux/util-linux.git/commit/?id=a3e40c14651fccf18e7954f081e601389baefe3f

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Karel Zak <kzak@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Martin Mares <mj@ucw.cz>
Cc: linux-video@atrey.karlin.mff.cuni.cz
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Link: https://lore.kernel.org/r/20200918015640.8439-3-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24 10:50:31 -06:00
Randy Dunlap
497de97e92 Documentation/admin-guide: kernel-parameters: capitalize Korina
Fix typo, capitalize Korina proper noun.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Link: https://lore.kernel.org/r/20200918054722.28713-1-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24 10:48:24 -06:00
Randy Dunlap
622381e62d Documentation: admin-guide: kernel-parameters: reformat "lapic=" boot option
Reformat "lapic=" to try to make it more understandable and similar
to the style that is mostly used in this file.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20200918054739.2523-1-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24 10:48:02 -06:00
Randy Dunlap
7c42376e07 Documentation/admin-guide: kernel-parameters: fix "io7" parameter description
Fix punctuation and capitalization for the "io7" boot parameter.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Link: https://lore.kernel.org/r/20200918054751.6538-1-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24 10:46:51 -06:00
Randy Dunlap
255bf90f84 Documentation/admin-guide: kernel-parameters: fix "disable_ddw" wording
Drop and extraneous word (if) in a sentence.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Link: https://lore.kernel.org/r/20200918054803.6588-1-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24 10:46:15 -06:00
Tian Tao
c372e741ae Documentation: Remove CMA's dependency on architecture
CMA only depends on MMU. It doesn't depend on arch too much. such as ARM,
ARM64, X86, MIPS etc. so We remove the dependency of cma about the
architecture in kernel-parameters.txt.

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/1600412758-60545-1-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24 10:44:53 -06:00
Randy Dunlap
4276948867 Documentation: kernel-parameters: fix formatting of MIPS "machtype"
For the "machtype" boot parameter,
fix word spacing, line wrap, and plural of "laptops".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Link: https://lore.kernel.org/r/c9059e35-188d-a749-1907-767b53479328@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24 10:38:40 -06:00
Satheesh Rajendran
aed26eebf5 Doc: admin-guide: Add entry for kvm_cma_resv_ratio kernel param
Add document entry for kvm_cma_resv_ratio kernel param which
is used to alter the KVM contiguous memory allocation percentage
for hash pagetable allocation used by hash mode PowerPC KVM guests.

Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Link: https://lore.kernel.org/r/20200921090220.14981-1-sathnaga@linux.vnet.ibm.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24 10:36:49 -06:00
Tian Tao
5b280ed427 Documentation: arm64 also supports disable hugeiomap
arm64 also supports disable hugeiomap,updated documentation.

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Link: https://lore.kernel.org/r/1599740386-47210-1-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-16 12:21:00 -06:00
Arvind Sankar
0a4bb5e550 x86/fpu: Allow multiple bits in clearcpuid= parameter
Commit

  0c2a3913d6 ("x86/fpu: Parse clearcpuid= as early XSAVE argument")

changed clearcpuid parsing from __setup() to cmdline_find_option().
While the __setup() function would have been called for each clearcpuid=
parameter on the command line, cmdline_find_option() will only return
the last one, so the change effectively made it impossible to disable
more than one bit.

Allow a comma-separated list of bit numbers as the argument for
clearcpuid to allow multiple bits to be disabled again. Log the bits
being disabled for informational purposes.

Also fix the check on the return value of cmdline_find_option(). It
returns -1 when the option is not found, so testing as a boolean is
incorrect.

Fixes: 0c2a3913d6 ("x86/fpu: Parse clearcpuid= as early XSAVE argument")
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200907213919.2423441-1-nivedita@alum.mit.edu
2020-09-10 18:32:05 +02:00
Paul E. McKenney
6fe208f63a Merge branch 'csd.2020.09.04a' into HEAD
csd.2020.09.04a: CPU smp_call_function() torture tests.
2020-09-04 11:54:52 -07:00
Paul E. McKenney
7fbe67e46a Merge branch 'strictgp.2020.08.24a' into HEAD
strictgp.2020.08.24a: Strict grace periods for KASAN testing.
2020-09-03 09:47:42 -07:00
Paul E. McKenney
f511ce1424 Merge branch 'scftorture.2020.08.24a' into HEAD
scftorture.2020.08.24a: Torture tests for smp_call_function() and friends.
2020-09-03 09:47:01 -07:00
Barry Song
b7176c261c dma-contiguous: provide the ability to reserve per-numa CMA
Right now, drivers like ARM SMMU are using dma_alloc_coherent() to get
coherent DMA buffers to save their command queues and page tables. As
there is only one default CMA in the whole system, SMMUs on nodes other
than node0 will get remote memory. This leads to significant latency.

This patch provides per-numa CMA so that drivers like SMMU can get local
memory. Tests show localizing CMA can decrease dma_unmap latency much.
For instance, before this patch, SMMU on node2  has to wait for more than
560ns for the completion of CMD_SYNC in an empty command queue; with this
patch, it needs 240ns only.

A positive side effect of this patch would be improving performance even
further for those users who are worried about performance more than DMA
security and use iommu.passthrough=1 to skip IOMMU. With local CMA, all
drivers can get local coherent DMA buffers.

Also, this patch changes the default CONFIG_CMA_AREAS to 19 in NUMA. As
1+CONFIG_CMA_AREAS should be quite enough for most servers on the market
even they enable both hugetlb_cma and pernuma_cma.
2 numa nodes: 2(hugetlb) + 2(pernuma) + 1(default global cma) = 5
4 numa nodes: 4(hugetlb) + 4(pernuma) + 1(default global cma) = 9
8 numa nodes: 8(hugetlb) + 8(pernuma) + 1(default global cma) = 17

Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-09-01 09:19:28 +02:00
Mahesh Bandewar
316cdaa115 net: add option to not create fall-back tunnels in root-ns as well
The sysctl that was added  earlier by commit 79134e6ce2 ("net: do
not create fallback tunnels for non-default namespaces") to create
fall-back only in root-ns. This patch enhances that behavior to provide
option not to create fallback tunnels in root-ns as well. Since modules
that create fallback tunnels could be built-in and setting the sysctl
value after booting is pointless, so added a kernel cmdline options to
change this default. The default setting is preseved for backward
compatibility. The kernel command line option of fb_tunnels=initns will
set the sysctl value to 1 and will create fallback tunnels only in initns
while kernel cmdline fb_tunnels=none will set the sysctl value to 2 and
fallback tunnels are skipped in every netns.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Maciej Zenczykowski <maze@google.com>
Cc: Jian Yang <jianyang@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-28 06:52:44 -07:00
Paul E. McKenney
d685514260 rcutorture: Allow pointer leaks to test diagnostic code
This commit adds an rcutorture.leakpointer module parameter that
intentionally leaks an RCU-protected pointer out of the RCU read-side
critical section and checks to see if the corresponding grace period
has elapsed, emitting a WARN_ON_ONCE() if so.  This module parameter can
be used to test facilities like CONFIG_RCU_STRICT_GRACE_PERIOD that end
grace periods quickly.

While in the area, also document rcutorture.irqreader, which was
previously left out.

Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-08-24 18:45:36 -07:00
Paul E. McKenney
3d29aaf1ef rcu: Provide optional RCU-reader exit delay for strict GPs
The goal of this series is to increase the probability of tools like
KASAN detecting that an RCU-protected pointer was used outside of its
RCU read-side critical section.  Thus far, the approach has been to make
grace periods and callback processing happen faster.  Another approach
is to delay the pointer leaker.  This commit therefore allows a delay
to be applied to exit from RCU read-side critical sections.

This slowdown is specified by a new rcutree.rcu_unlock_delay kernel boot
parameter that specifies this delay in microseconds, defaulting to zero.

Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-08-24 18:40:27 -07:00
Paul E. McKenney
4e88ec4a9e rcuperf: Change rcuperf to rcuscale
This commit further avoids conflation of rcuperf with the kernel's perf
feature by renaming kernel/rcu/rcuperf.c to kernel/rcu/rcuscale.c, and
also by similarly renaming the functions and variables inside this file.
This has the side effect of changing the names of the kernel boot
parameters, so kernel-parameters.txt and ver_functions.sh are also
updated.  The rcutorture --torture type was also updated from rcuperf
to rcuscale.

[ paulmck: Fix bugs located by Stephen Rothwell. ]
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-08-24 18:39:24 -07:00