linux.git/include/asm-generic, branch v5.7.15

x86, vmlinux.lds: Page-align end of ..page_aligned sections

2020-07-29T08:19:59+00:00

commit de2b41be8fcccb2f5b6c480d35df590476344201 upstream.

On x86-32 the idt_table with 256 entries needs only 2048 bytes. It is
page-aligned, but the end of the .bss..page_aligned section is not
guaranteed to be page-aligned.

As a result, objects from other .bss sections may end up on the same 4k
page as the idt_table, and will accidentially get mapped read-only during
boot, causing unexpected page-faults when the kernel writes to them.

This could be worked around by making the objects in the page aligned
sections page sized, but that's wrong.

Explicit sections which store only page aligned objects have an implicit
guarantee that the object is alone in the page in which it is placed. That
works for all objects except the last one. That's inconsistent.

Enforcing page sized objects for these sections would wreckage memory
sanitizers, because the object becomes artificially larger than it should
be and out of bound access becomes legit.

Align the end of the .bss..page_aligned and .data..page_aligned section on
page-size so all objects places in these sections are guaranteed to have
their own page.

[ tglx: Amended changelog ]

Signed-off-by: Joerg Roedel 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Kees Cook 
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200721093448.10417-1-joro@8bytes.org
Signed-off-by: Greg Kroah-Hartman

asm-generic/mmiowb: Allow mmiowb_set_pending() when preemptible()

2020-07-29T08:19:54+00:00

[ Upstream commit bd024e82e4cd95c7f1a475a55f99871936c2b2db ]

Although mmiowb() is concerned only with serialising MMIO writes occuring
in contexts where a spinlock is held, the call to mmiowb_set_pending()
from the MMIO write accessors can occur in preemptible contexts, such
as during driver probe() functions where ordering between CPUs is not
usually a concern, assuming that the task migration path provides the
necessary ordering guarantees.

Unfortunately, the default implementation of mmiowb_set_pending() is not
preempt-safe, as it makes use of a a per-cpu variable to track its
internal state. This has been reported to generate the following splat
on riscv:

 | BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1
 | caller is regmap_mmio_write32le+0x1c/0x46
 | CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc3-hfu+ #1
 | Call Trace:
 |  walk_stackframe+0x0/0x7a
 |  dump_stack+0x6e/0x88
 |  regmap_mmio_write32le+0x18/0x46
 |  check_preemption_disabled+0xa4/0xaa
 |  regmap_mmio_write32le+0x18/0x46
 |  regmap_mmio_write+0x26/0x44
 |  regmap_write+0x28/0x48
 |  sifive_gpio_probe+0xc0/0x1da

Although it's possible to fix the driver in this case, other splats have
been seen from other drivers, including the infamous 8250 UART, and so
it's better to address this problem in the mmiowb core itself.

Fix mmiowb_set_pending() by using the raw_cpu_ptr() to get at the mmiowb
state and then only updating the 'mmiowb_pending' field if we are not
preemptible (i.e. we have a non-zero nesting count).

Cc: Arnd Bergmann 
Cc: Paul Walmsley 
Cc: Guo Ren 
Cc: Michael Ellerman 
Reported-by: Palmer Dabbelt 
Reported-by: Emil Renner Berthing 
Tested-by: Emil Renner Berthing 
Reviewed-by: Palmer Dabbelt 
Acked-by: Palmer Dabbelt 
Link: https://lore.kernel.org/r/20200716112816.7356-1-will@kernel.org
Signed-off-by: Will Deacon 
Signed-off-by: Sasha Levin

include/asm-generic/topology.h: guard cpumask_of_node() macro argument

2020-05-28T18:35:41+00:00

drivers/hwmon/amd_energy.c:195:15: error: invalid operands to binary expression ('void' and 'int')
                                        (channel - data->nr_cpus));
                                        ~~~~~~~~~^~~~~~~~~~~~~~~~~
include/asm-generic/topology.h:51:42: note: expanded from macro 'cpumask_of_node'
    #define cpumask_of_node(node)       ((void)node, cpu_online_mask)
                                               ^~~~
include/linux/cpumask.h:618:72: note: expanded from macro 'cpumask_first_and'
 #define cpumask_first_and(src1p, src2p) cpumask_next_and(-1, (src1p), (src2p))
                                                                       ^~~~~

Fixes: f0b848ce6fe9 ("cpumask: Introduce cpumask_of_{node,pcibus} to replace {node,pcibus}_to_cpumask")
Fixes: 8abee9566b7e ("hwmon: Add amd_energy driver to report energy counters")
Signed-off-by: Arnd Bergmann 
Signed-off-by: Andrew Morton 
Acked-by: Guenter Roeck 
Link: http://lkml.kernel.org/r/20200527134623.930247-1-arnd@arndb.de
Signed-off-by: Linus Torvalds

arch: split MODULE_ARCH_VERMAGIC definitions out to

2020-04-23T01:50:26+00:00

As the bug report [1] pointed out,  must be included
after .

I believe we should not impose any include order restriction. We often
sort include directives alphabetically, but it is just coding style
convention. Technically, we can include header files in any order by
making every header self-contained.

Currently, arch-specific MODULE_ARCH_VERMAGIC is defined in
, which is not included from .

Hence, the straight-forward fix-up would be as follows:

|--- a/include/linux/vermagic.h
|+++ b/include/linux/vermagic.h
|@@ -1,5 +1,6 @@
| /* SPDX-License-Identifier: GPL-2.0 */
| #include 
|+#include 
|
| /* Simply sanity version stamp for modules. */
| #ifdef CONFIG_SMP

This works enough, but for further cleanups, I split MODULE_ARCH_VERMAGIC
definitions into .

With this,  and  will be orthogonal,
and the location of MODULE_ARCH_VERMAGIC definitions will be consistent.

For arc and ia64, MODULE_PROC_FAMILY is only used for defining
MODULE_ARCH_VERMAGIC. I squashed it.

For hexagon, nds32, and xtensa, I removed  entirely
because they contained nothing but MODULE_ARCH_VERMAGIC definition.
Kbuild will automatically generate  at build-time,
wrapping .

[1] https://lore.kernel.org/lkml/20200411155623.GA22175@zn.tnic

Reported-by: Borislav Petkov 
Signed-off-by: Masahiro Yamada 
Acked-by: Jessica Yu

Merge tag 'hyperv-fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

2020-04-14T18:58:04+00:00

Pull hyperv fixes from Wei Liu:

 - a series from Tianyu Lan to fix crash reporting on Hyper-V

 - three miscellaneous cleanup patches

* tag 'hyperv-fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
  x86/Hyper-V: Report crash data in die() when panic_on_oops is set
  x86/Hyper-V: Report crash register data when sysctl_record_panic_msg is not set
  x86/Hyper-V: Report crash register data or kmsg before running crash kernel
  x86/Hyper-V: Trigger crash enlightenment only once during system crash.
  x86/Hyper-V: Free hv_panic_page when fail to register kmsg dump
  x86/Hyper-V: Unload vmbus channel in hv panic callback
  x86: hyperv: report value of misc_features
  hv_debugfs: Make hv_debug_root static
  hv: hyperv_vmbus.h: Replace zero-length array with flexible-array member

x86/Hyper-V: Report crash data in die() when panic_on_oops is set

2020-04-11T16:19:07+00:00

When oops happens with panic_on_oops unset, the oops
thread is killed by die() and system continues to run.
In such case, guest should not report crash register
data to host since system still runs. Check panic_on_oops
and return directly in hyperv_report_panic() when the function
is called in the die() and panic_on_oops is unset. Fix it.

Fixes: 7ed4325a44ea ("Drivers: hv: vmbus: Make panic reporting to be more useful")
Signed-off-by: Tianyu Lan 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20200406155331.2105-7-Tianyu.Lan@microsoft.com
Signed-off-by: Wei Liu

userfaultfd: wp: add pmd_swp_*uffd_wp() helpers

2020-04-07T17:43:39+00:00

Adding these missing helpers for uffd-wp operations with pmd
swap/migration entries.

Signed-off-by: Peter Xu 
Signed-off-by: Andrew Morton 
Reviewed-by: Jerome Glisse 
Reviewed-by: Mike Rapoport 
Cc: Andrea Arcangeli 
Cc: Bobby Powers 
Cc: Brian Geffon 
Cc: David Hildenbrand 
Cc: Denis Plotnikov 
Cc: "Dr . David Alan Gilbert" 
Cc: Hugh Dickins 
Cc: Johannes Weiner 
Cc: "Kirill A . Shutemov" 
Cc: Martin Cracauer 
Cc: Marty McFadden 
Cc: Maya Gokhale 
Cc: Mel Gorman 
Cc: Mike Kravetz 
Cc: Pavel Emelyanov 
Cc: Rik van Riel 
Cc: Shaohua Li 
Link: http://lkml.kernel.org/r/20200220163112.11409-10-peterx@redhat.com
Signed-off-by: Linus Torvalds

userfaultfd: wp: add WP pagetable tracking to x86

2020-04-07T17:43:39+00:00

Accurate userfaultfd WP tracking is possible by tracking exactly which
virtual memory ranges were writeprotected by userland.  We can't relay
only on the RW bit of the mapped pagetable because that information is
destroyed by fork() or KSM or swap.  If we were to relay on that, we'd
need to stay on the safe side and generate false positive wp faults for
every swapped out page.

[peterx@redhat.com: append _PAGE_UFD_WP to _PAGE_CHG_MASK]
Signed-off-by: Andrea Arcangeli 
Signed-off-by: Peter Xu 
Signed-off-by: Andrew Morton 
Reviewed-by: Jerome Glisse 
Reviewed-by: Mike Rapoport 
Cc: Bobby Powers 
Cc: Brian Geffon 
Cc: David Hildenbrand 
Cc: Denis Plotnikov 
Cc: "Dr . David Alan Gilbert" 
Cc: Hugh Dickins 
Cc: Johannes Weiner 
Cc: "Kirill A . Shutemov" 
Cc: Martin Cracauer 
Cc: Marty McFadden 
Cc: Maya Gokhale 
Cc: Mel Gorman 
Cc: Mike Kravetz 
Cc: Pavel Emelyanov 
Cc: Rik van Riel 
Cc: Shaohua Li 
Link: http://lkml.kernel.org/r/20200220163112.11409-4-peterx@redhat.com
Signed-off-by: Linus Torvalds

mm/vma: replace all remaining open encodings with is_vm_hugetlb_page()

2020-04-07T17:43:37+00:00

This replaces all remaining open encodings with is_vm_hugetlb_page().

Signed-off-by: Anshuman Khandual 
Signed-off-by: Andrew Morton 
Acked-by: Vlastimil Babka 
Cc: Paul Mackerras 
Cc: Benjamin Herrenschmidt 
Cc: Michael Ellerman 
Cc: Alexander Viro 
Cc: Will Deacon 
Cc: "Aneesh Kumar K.V" 
Cc: Nick Piggin 
Cc: Peter Zijlstra 
Cc: Arnd Bergmann 
Cc: Ingo Molnar 
Cc: Arnaldo Carvalho de Melo 
Cc: Andy Lutomirski 
Cc: Dave Hansen 
Cc: Geert Uytterhoeven 
Cc: Guo Ren 
Cc: Mel Gorman 
Cc: Paul Burton 
Cc: Paul Mackerras 
Cc: Ralf Baechle 
Cc: Rich Felker 
Cc: Steven Rostedt 
Cc: Thomas Gleixner 
Cc: Yoshinori Sato 
Link: http://lkml.kernel.org/r/1582520593-30704-4-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds

Merge tag 'gpio-v5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

2020-04-04T17:27:00+00:00

Pull GPIO updates from Linus Walleij:
"This is the bulk of GPIO development for the v5.7 kernel cycle.

Core and userspace API:

- The userspace API KFIFOs have been imoproved with locks that do not
block interrupts. This makes us better at getting events to
userspace without blocking or disturbing new events arriving in the
same time. This was reviewed by the KFIFO maintainer Stefani. This
is a generic improvement which paves the road for similar
improvements in other subsystems.

- We provide a new ioctl() for monitoring changes in the line
information, such as when multiple clients are taking lines and
giving them back, possibly reconfiguring them in the process: we
can now monitor that and not get stuck with stale static
information.

- An example tool 'gpio-watch' is provided to showcase this
functionality.

- Timestamps for events are switched to ktime_get_ns() which is
monotonic. We previously had a 'realtime' stamp which could move
forward and *backward* in time, which probably would just cause
silent bugs and weird behaviour. In the long run we see two
relevant timestamps: ktime_get_ns() or the timestamp sometimes
provided by the GPIO hardware itself, if that exists.

- Device Tree overlay support for GPIO hogs. On systems that load
overlays, these overlays can now contain hogs, and will then be
respected.

- Handle pin control interaction with nonexisting pin ranges in the
GPIO library core instead of in the individual drivers.

New drivers:

- New driver for the Mellanox BlueField 2 GPIO controller.

Driver improvements:

- Introduce the BGPIOF_NO_SET_ON_INPUT flag to the generic MMIO GPIO
library and use this flag in the MT7621 driver.

- Texas Instruments OMAP CPU power management improvements, such as
blocking of idle on pending GPIO interrupts"

* tag 'gpio-v5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (59 commits)
Revert "gpio: eic-sprd: Use devm_platform_ioremap_resource()"
pinctrl: Unconditionally assign .request()/.free()
gpio: Unconditionally assign .request()/.free()
gpio: export of_pinctrl_get to modules
pinctrl: Define of_pinctrl_get() dummy for !PINCTRL
gpio: Rename variable in core APIs
gpio: Avoid using pin ranges with !PINCTRL
gpiolib: Remove unused gpio_chip parameter from gpio_set_bias()
gpiolib: Pass gpio_desc to gpio_set_config()
gpiolib: Introduce gpiod_set_config()
tools: gpio: Fix out-of-tree build regression
gpio: gpiolib: fix a doc warning
gpio: tegra186: Add Tegra194 pin ranges for GG.0 and GG.1
gpio: tegra186: Add support for pin ranges
gpio: Support GPIO controllers without pin-ranges
ARM: integrator: impd1: Use GPIO_LOOKUP() helper macro
gpio: brcmstb: support gpio-line-names property
tools: gpio: Fix typo in gpio-utils
tools: gpio-hammer: Apply scripts/Lindent and retain good changes
gpiolib: gpio_name_to_desc: factor out !name check
...