Linux kernel
============
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several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
code
Clone this repository
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In commit 4ed28639519c ("fs, elf: drop MAP_FIXED usage from elf_map") we
changed elf to use MAP_FIXED_NOREPLACE instead of MAP_FIXED for the
executable mappings.
Then, people reported that it broke some binaries that had overlapping
segments from the same file, and commit ad55eac74f20 ("elf: enforce
MAP_FIXED on overlaying elf segments") re-instated MAP_FIXED for some
overlaying elf segment cases. But only some - despite the summary line
of that commit, it only did it when it also does a temporary brk vma for
one obvious overlapping case.
Now Russell King reports another overlapping case with old 32-bit x86
binaries, which doesn't trigger that limited case. End result: we had
better just drop MAP_FIXED_NOREPLACE entirely, and go back to MAP_FIXED.
Yes, it's a sign of old binaries generated with old tool-chains, but we
do pride ourselves on not breaking existing setups.
This still leaves MAP_FIXED_NOREPLACE in place for the load_elf_interp()
and the old load_elf_library() use-cases, because nobody has reported
breakage for those. Yet.
Note that in all the cases seen so far, the overlapping elf sections
seem to be just re-mapping of the same executable with different section
attributes. We could possibly introduce a new MAP_FIXED_NOFILECHANGE
flag or similar, which acts like NOREPLACE, but allows just remapping
the same executable file using different protection flags.
It's not clear that would make a huge difference to anything, but if
people really hate that "elf remaps over previous maps" behavior, maybe
at least a more limited form of remapping would alleviate some concerns.
Alternatively, we should take a look at our elf_map() logic to see if we
end up not mapping things properly the first time.
In the meantime, this is the minimal "don't do that then" patch while
people hopefully think about it more.
Reported-by: Russell King <linux@armlinux.org.uk>
Fixes: 4ed28639519c ("fs, elf: drop MAP_FIXED usage from elf_map")
Fixes: ad55eac74f20 ("elf: enforce MAP_FIXED on overlaying elf segments")
Cc: Michal Hocko <mhocko@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull dma-mapping regression fix from Christoph Hellwig:
"Revert an incorret hunk from a patch that caused problems on various
arm boards (Andrey Smirnov)"
* tag 'dma-mapping-5.4-1' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: fix false positive warnings in dma_common_free_remap()
Pull ARM SoC fixes from Olof Johansson:
"A few fixes this time around:
- Fixup of some clock specifications for DRA7 (device-tree fix)
- Removal of some dead/legacy CPU OPP/PM code for OMAP that throws
warnings at boot
- A few more minor fixups for OMAPs, most around display
- Enable STM32 QSPI as =y since their rootfs sometimes comes from
there
- Switch CONFIG_REMOTEPROC to =y since it went from tristate to bool
- Fix of thermal zone definition for ux500 (5.4 regression)"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
ARM: multi_v7_defconfig: Fix SPI_STM32_QSPI support
ARM: dts: ux500: Fix up the CPU thermal zone
arm64/ARM: configs: Change CONFIG_REMOTEPROC from m to y
ARM: dts: am4372: Set memory bandwidth limit for DISPC
ARM: OMAP2+: Fix warnings with broken omap2_set_init_voltage()
ARM: OMAP2+: Add missing LCDC midlemode for am335x
ARM: OMAP2+: Fix missing reset done flag for am3 and am43
ARM: dts: Fix gpio0 flags for am335x-icev2
ARM: omap2plus_defconfig: Enable more droid4 devices as loadable modules
ARM: omap2plus_defconfig: Enable DRM_TI_TFP410
DTS: ARM: gta04: introduce legacy spi-cs-high to make display work again
ARM: dts: Fix wrong clocks for dra7 mcasp
clk: ti: dra7: Fix mcasp8 clock bits
Commit 5cf4537975bb ("dma-mapping: introduce a dma_common_find_pages
helper") changed invalid input check in dma_common_free_remap() from:
if (!area || !area->flags != VM_DMA_COHERENT)
to
if (!area || !area->flags != VM_DMA_COHERENT || !area->pages)
which seem to produce false positives for memory obtained via
dma_common_contiguous_remap()
This triggers the following warning message when doing "reboot" on ZII
VF610 Dev Board Rev B:
WARNING: CPU: 0 PID: 1 at kernel/dma/remap.c:112 dma_common_free_remap+0x88/0x8c
trying to free invalid coherent area: 9ef82980
Modules linked in:
CPU: 0 PID: 1 Comm: systemd-shutdow Not tainted 5.3.0-rc6-next-20190820 #119
Hardware name: Freescale Vybrid VF5xx/VF6xx (Device Tree)
Backtrace:
[<8010d1ec>] (dump_backtrace) from [<8010d588>] (show_stack+0x20/0x24)
r7:8015ed78 r6:00000009 r5:00000000 r4:9f4d9b14
[<8010d568>] (show_stack) from [<8077e3f0>] (dump_stack+0x24/0x28)
[<8077e3cc>] (dump_stack) from [<801197a0>] (__warn.part.3+0xcc/0xe4)
[<801196d4>] (__warn.part.3) from [<80119830>] (warn_slowpath_fmt+0x78/0x94)
r6:00000070 r5:808e540c r4:81c03048
[<801197bc>] (warn_slowpath_fmt) from [<8015ed78>] (dma_common_free_remap+0x88/0x8c)
r3:9ef82980 r2:808e53e0
r7:00001000 r6:a0b1e000 r5:a0b1e000 r4:00001000
[<8015ecf0>] (dma_common_free_remap) from [<8010fa9c>] (remap_allocator_free+0x60/0x68)
r5:81c03048 r4:9f4d9b78
[<8010fa3c>] (remap_allocator_free) from [<801100d0>] (__arm_dma_free.constprop.3+0xf8/0x148)
r5:81c03048 r4:9ef82900
[<8010ffd8>] (__arm_dma_free.constprop.3) from [<80110144>] (arm_dma_free+0x24/0x2c)
r5:9f563410 r4:80110120
[<80110120>] (arm_dma_free) from [<8015d80c>] (dma_free_attrs+0xa0/0xdc)
[<8015d76c>] (dma_free_attrs) from [<8020f3e4>] (dma_pool_destroy+0xc0/0x154)
r8:9efa8860 r7:808f02f0 r6:808f02d0 r5:9ef82880 r4:9ef82780
[<8020f324>] (dma_pool_destroy) from [<805525d0>] (ehci_mem_cleanup+0x6c/0x150)
r7:9f563410 r6:9efa8810 r5:00000000 r4:9efd0148
[<80552564>] (ehci_mem_cleanup) from [<80558e0c>] (ehci_stop+0xac/0xc0)
r5:9efd0148 r4:9efd0000
[<80558d60>] (ehci_stop) from [<8053c4bc>] (usb_remove_hcd+0xf4/0x1b0)
r7:9f563410 r6:9efd0074 r5:81c03048 r4:9efd0000
[<8053c3c8>] (usb_remove_hcd) from [<8056361c>] (host_stop+0x48/0xb8)
r7:9f563410 r6:9efd0000 r5:9f5f4040 r4:9f5f5040
[<805635d4>] (host_stop) from [<80563d0c>] (ci_hdrc_host_destroy+0x34/0x38)
r7:9f563410 r6:9f5f5040 r5:9efa8800 r4:9f5f4040
[<80563cd8>] (ci_hdrc_host_destroy) from [<8055ef18>] (ci_hdrc_remove+0x50/0x10c)
[<8055eec8>] (ci_hdrc_remove) from [<804a2ed8>] (platform_drv_remove+0x34/0x4c)
r7:9f563410 r6:81c4f99c r5:9efa8810 r4:9efa8810
[<804a2ea4>] (platform_drv_remove) from [<804a18a8>] (device_release_driver_internal+0xec/0x19c)
r5:00000000 r4:9efa8810
[<804a17bc>] (device_release_driver_internal) from [<804a1978>] (device_release_driver+0x20/0x24)
r7:9f563410 r6:81c41ed0 r5:9efa8810 r4:9f4a1dac
[<804a1958>] (device_release_driver) from [<804a01b8>] (bus_remove_device+0xdc/0x108)
[<804a00dc>] (bus_remove_device) from [<8049c204>] (device_del+0x150/0x36c)
r7:9f563410 r6:81c03048 r5:9efa8854 r4:9efa8810
[<8049c0b4>] (device_del) from [<804a3368>] (platform_device_del.part.2+0x20/0x84)
r10:9f563414 r9:809177e0 r8:81cb07dc r7:81c78320 r6:9f563454 r5:9efa8800
r4:9efa8800
[<804a3348>] (platform_device_del.part.2) from [<804a3420>] (platform_device_unregister+0x28/0x34)
r5:9f563400 r4:9efa8800
[<804a33f8>] (platform_device_unregister) from [<8055dce0>] (ci_hdrc_remove_device+0x1c/0x30)
r5:9f563400 r4:00000001
[<8055dcc4>] (ci_hdrc_remove_device) from [<805652ac>] (ci_hdrc_imx_remove+0x38/0x118)
r7:81c78320 r6:9f563454 r5:9f563410 r4:9f541010
[<8056538c>] (ci_hdrc_imx_shutdown) from [<804a2970>] (platform_drv_shutdown+0x2c/0x30)
[<804a2944>] (platform_drv_shutdown) from [<8049e4fc>] (device_shutdown+0x158/0x1f0)
[<8049e3a4>] (device_shutdown) from [<8013ac80>] (kernel_restart_prepare+0x44/0x48)
r10:00000058 r9:9f4d8000 r8:fee1dead r7:379ce700 r6:81c0b280 r5:81c03048
r4:00000000
[<8013ac3c>] (kernel_restart_prepare) from [<8013ad14>] (kernel_restart+0x1c/0x60)
[<8013acf8>] (kernel_restart) from [<8013af84>] (__do_sys_reboot+0xe0/0x1d8)
r5:81c03048 r4:00000000
[<8013aea4>] (__do_sys_reboot) from [<8013b0ec>] (sys_reboot+0x18/0x1c)
r8:80101204 r7:00000058 r6:00000000 r5:00000000 r4:00000000
[<8013b0d4>] (sys_reboot) from [<80101000>] (ret_fast_syscall+0x0/0x54)
Exception stack(0x9f4d9fa8 to 0x9f4d9ff0)
9fa0: 00000000 00000000 fee1dead 28121969 01234567 379ce700
9fc0: 00000000 00000000 00000000 00000058 00000000 00000000 00000000 00016d04
9fe0: 00028e0c 7ec87c64 000135ec 76c1f410
Restore original invalid input check in dma_common_free_remap() to
avoid this problem.
Fixes: 5cf4537975bb ("dma-mapping: introduce a dma_common_find_pages helper")
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
[hch: just revert the offending hunk instead of creating a new helper]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull Kbuild fixes from Masahiro Yamada:
- remove unneeded ar-option and KBUILD_ARFLAGS
- remove long-deprecated SUBDIRS
- fix modpost to suppress false-positive warnings for UML builds
- fix namespace.pl to handle relative paths to ${objtree}, ${srctree}
- make setlocalversion work for /bin/sh
- make header archive reproducible
- fix some Makefiles and documents
* tag 'kbuild-fixes-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kheaders: make headers archive reproducible
kbuild: update compile-test header list for v5.4-rc2
kbuild: two minor updates for Documentation/kbuild/modules.rst
scripts/setlocalversion: clear local variable to make it work for sh
namespace: fix namespace.pl script to support relative paths
video/logo: do not generate unneeded logo C files
video/logo: remove unneeded *.o pattern from clean-files
integrity: remove pointless subdir-$(CONFIG_...)
integrity: remove unneeded, broken attempt to add -fshort-wchar
modpost: fix static EXPORT_SYMBOL warnings for UML build
kbuild: correct formatting of header in kbuild module docs
kbuild: remove SUBDIRS support
kbuild: remove ar-option and KBUILD_ARFLAGS
SPI_STM32_QSPI must be set in buildin as rootfs can be
located on QSPI memory device.
Link: https://lore.kernel.org/r/20191004124025.17394-1-patrice.chotard@st.com
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
Pull MIPS fixes from Paul Burton:
- Build fixes for Cavium Octeon & PMC-Sierra MSP systems, as well as
all pre-MIPSr6 configurations built with binutils < 2.25.
- Boot fixes for 64-bit Loongson systems & SGI IP28 systems.
- Wire up the new clone3 syscall.
- Clean ups for a few build-time warnings.
* tag 'mips_fixes_5.4_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
MIPS: fw/arc: Remove unused addr variable
MIPS: pmcs-msp71xx: Remove unused addr variable
MIPS: pmcs-msp71xx: Add missing MAX_PROM_MEM definition
mips: Loongson: Fix the link time qualifier of 'serial_exit()'
MIPS: init: Prevent adding memory before PHYS_OFFSET
MIPS: init: Fix reservation of memory between PHYS_OFFSET and mem start
MIPS: VDSO: Fix build for binutils < 2.25
MIPS: VDSO: Remove unused gettimeofday.c
MIPS: Wire up clone3 syscall
MIPS: octeon: Include required header; fix octeon ethernet build
MIPS: cpu-bugs64: Mark inline functions as __always_inline
MIPS: dts: ar9331: fix interrupt-controller size
MIPS: Loongson64: Fix boot failure after dropping boot_mem_map
Pull SCSI fixes from James Bottomley:
"Twelve patches mostly small but obvious fixes or cosmetic but small
updates"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: qla2xxx: Fix Nport ID display value
scsi: qla2xxx: Fix N2N link up fail
scsi: qla2xxx: Fix N2N link reset
scsi: qla2xxx: Optimize NPIV tear down process
scsi: qla2xxx: Fix stale mem access on driver unload
scsi: qla2xxx: Fix unbound sleep in fcport delete path.
scsi: qla2xxx: Silence fwdump template message
scsi: hisi_sas: Make three functions static
scsi: megaraid: disable device when probe failed after enabled device
scsi: storvsc: setup 1:1 mapping between hardware queue and CPU queue
scsi: qedf: Remove always false 'tmp_prio < 0' statement
scsi: ufs: skip shutdown if hba is not powered
scsi: bnx2fc: Handle scope bits when array returns BUSY or TSF
In commit 43d8ce9d65a5 ("Provide in-kernel headers to make
extending kernel easier") a new mechanism was introduced, for kernels
>=5.2, which embeds the kernel headers in the kernel image or a module
and exposes them in procfs for use by userland tools.
The archive containing the header files has nondeterminism caused by
header files metadata. This patch normalizes the metadata and utilizes
KBUILD_BUILD_TIMESTAMP if provided and otherwise falls back to the
default behaviour.
In commit f7b101d33046 ("kheaders: Move from proc to sysfs") it was
modified to use sysfs and the script for generation of the archive was
renamed to what is being patched.
Signed-off-by: Dmitry Goldin <dgoldin+lkml@protonmail.ch>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Fixes for omaps for v5.4-rc cycle
Here are fixes for omaps to deal with few regressions, and to fix
more boot time errors and warnings:
- The recent ti-sysc interconnect target module driver changes had
incorrect clock bits for both clocks and dts that cause warnings
- For omap3-gta04, gpio changes caused the LCD to break a while back,
and after discussing things the right fix is to set spi-cs-high
- Recent omapdrm changes to use generic panels caused tfp410 to be
disabled as we now must enable the generic support for it in
defconfig
- Recent omapdrm and backlight changes also finally made droid4 LCD
to work, so let's enable it in the defconfig it can be used out
of the box. This is not strictly a fix, but we still also have the
older CONFIG_MFD_TI_LMU options available so this cuts down the
confusion for trying to guess which display and which backlight
is needed
- Recent ti-sysc interconnect target module changes need the gpio
module disabled on some boards, but this now needs to happen at
the module level, not at the gpio driver level
- Recent changes to probe system timers with ti-sysc caused warnings
about mismatch in syconfig registers, so let's configure the option
for RESET_STATUS as available in the TRMs
- Recent changes to probe LCDC with ti-sysc caused warnings about
mismatch in sysconfig registers, so let's configure the missing
idlemodes for both platform data and dts as documented in TRMs
- Since we moved mach-omap2 to probe with device tree, we've been
getting voltage controller warnings. Turns out this code is no
longer needed, so let's just remove omap2_set_init_voltage() to
get rid of the pointless warnings
- Configure am4372 dispc memory bandwidth to avoid underflow errors
* tag 'omap-for-v5.4/fixes-rc1-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
ARM: dts: am4372: Set memory bandwidth limit for DISPC
ARM: OMAP2+: Fix warnings with broken omap2_set_init_voltage()
ARM: OMAP2+: Add missing LCDC midlemode for am335x
ARM: OMAP2+: Fix missing reset done flag for am3 and am43
ARM: dts: Fix gpio0 flags for am335x-icev2
ARM: omap2plus_defconfig: Enable more droid4 devices as loadable modules
ARM: omap2plus_defconfig: Enable DRM_TI_TFP410
DTS: ARM: gta04: introduce legacy spi-cs-high to make display work again
ARM: dts: Fix wrong clocks for dra7 mcasp
clk: ti: dra7: Fix mcasp8 clock bits
Link: https://lore.kernel.org/r/pull-1570040410-308159@atomide.com
Signed-off-by: Olof Johansson <olof@lixom.net>
Pull RISC-V fixes from Paul Walmsley:
- Ensure that exclusive-load reservations are terminated after system
call or exception handling. This primarily affects QEMU, which does
not expire load reservations.
- Fix an issue primarily affecting RV32 platforms that can cause the DT
header to be corrupted, causing boot failures.
* tag 'riscv/for-v5.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: Fix memblock reservation for device tree blob
RISC-V: Clear load reservations while restoring hart contexts
The addr variable in prom_free_prom_memory() has been unused since
commit 0df1007677d5 ("MIPS: fw: Record prom memory"), leading to a
compiler warning:
arch/mips/fw/arc/memory.c:163:16:
warning: unused variable 'addr' [-Wunused-variable]
Fix this by removing the unused variable.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 0df1007677d5 ("MIPS: fw: Record prom memory")
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-mips@vger.kernel.org
This makes getdents() and getdents64() do sanity checking on the
pathname that it gives to user space. And to mitigate the performance
impact of that, it first cleans up the way it does the user copying, so
that the code avoids doing the SMAP/PAN updates between each part of the
dirent structure write.
I really wanted to do this during the merge window, but didn't have
time. The conversion of filldir to unsafe_put_user() is something I've
had around for years now in a private branch, but the extra pathname
checking finally made me clean it up to the point where it is mergable.
It's worth noting that the filename validity checking really should be a
bit smarter: it would be much better to delay the error reporting until
the end of the readdir, so that non-corrupted filenames are still
returned. But that involves bigger changes, so let's see if anybody
actually hits the corrupt directory entry case before worrying about it
further.
* branch 'readdir':
Make filldir[64]() verify the directory entry filename is valid
Convert filldir[64]() from __put_user() to unsafe_put_user()