linux-dev/arch/xtensa/configs, branch master

treewide: defconfig: address renamed CONFIG_DEBUG_INFO=y

2022-09-12T04:55:05Z

CONFIG_DEBUG_INFO is now implicitly selected if one picks one of the explicit options that could be DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT, DEBUG_INFO_DWARF4, DEBUG_INFO_DWARF5. This was actually not what I had in mind when I suggested making it a 'choice' statement, but it's too late to change again now, and the Kconfig logic is more sensible in the new form. Change any defconfig file that had CONFIG_DEBUG_INFO enabled but did not pick DWARF4 or DWARF5 explicitly to now pick the toolchain default. Link: https://lkml.kernel.org/r/20220811114609.2097335-1-arnd@kernel.org Fixes: f9b3cd245784 ("Kconfig.debug: make DEBUG_INFO selectable from a choice") Signed-off-by: Arnd Bergmann Reviewed-by: Kees Cook Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Cc: Vineet Gupta Cc: Michal Simek Cc: Thomas Bogendoerfer Cc: Dinh Nguyen Cc: Yoshinori Sato Cc: Rich Felker Cc: Richard Weinberger Cc: Anton Ivanov Cc: Johannes Berg Cc: Chris Zankel Cc: Max Filippov Cc: Arnd Bergmann Signed-off-by: Andrew Morton

rcu: Fix undefined Kconfig macros

2021-09-13T23:32:46Z

Invoking scripts/checkkconfigsymbols.py in the Linux-kernel source tree located the following issues: 1. TREE_PREEMPT_RCU Referencing files: arch/sh/configs/sdk7786_defconfig It should now be CONFIG_PREEMPT_RCU. Except that the CONFIG_PREEMPT=y in that same file implies CONFIG_PREEMPT_RCU=y. Therefore, delete the CONFIG_TREE_PREEMPT_RCU=y line. The reason is as follows: In kernel/rcu/Kconfig, we have config PREEMPT_RCU bool default y if PREEMPTION https://www.kernel.org/doc/Documentation/kbuild/kconfig-language.txt says, "The default value is only assigned to the config symbol if no other value was set by the user (via the input prompt above)." there is no prompt in config PREEMPT_RCU entry, so we are guaranteed to get CONFIG_PREEMPT_RCU=y when CONFIG_PREEMPT is present. 2. RCU_CPU_STALL_INFO Referencing files: arch/xtensa/configs/nommu_kc705_defconfig The old Kconfig option RCU_CPU_STALL_INFO was removed by commit 75c27f119b64 ("rcu: Remove CONFIG_RCU_CPU_STALL_INFO"), and the kernel now acts as if this Kconfig option was unconditionally enabled. 3. RCU_NOCB_CPU_ALL Referencing files: Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.rst This is an old snapshot of the code. I update this from the real rcu_prepare_for_idle() function in kernel/rcu/tree_plugin.h. This change was tested by invoking "make htmldocs". 4. RCU_TORTURE_TESTS Referencing files: kernel/rcu/rcutorture.c Forward-progress checking conflicts with CPU-stall testing, so we should complain at "modprobe rcutorture" when both are enabled. Signed-off-by: Zhouyi Zhou Signed-off-by: Paul E. McKenney

drivers/char: remove /dev/kmem for good

2021-05-07T07:26:34Z

Patch series "drivers/char: remove /dev/kmem for good". Exploring /dev/kmem and /dev/mem in the context of memory hot(un)plug and memory ballooning, I started questioning the existence of /dev/kmem. Comparing it with the /proc/kcore implementation, it does not seem to be able to deal with things like a) Pages unmapped from the direct mapping (e.g., to be used by secretmem) -> kern_addr_valid(). virt_addr_valid() is not sufficient. b) Special cases like gart aperture memory that is not to be touched -> mem_pfn_is_ram() Unless I am missing something, it's at least broken in some cases and might fault/crash the machine. Looks like its existence has been questioned before in 2005 and 2010 [1], after ~11 additional years, it might make sense to revive the discussion. CONFIG_DEVKMEM is only enabled in a single defconfig (on purpose or by mistake?). All distributions disable it: in Ubuntu it has been disabled for more than 10 years, in Debian since 2.6.31, in Fedora at least starting with FC3, in RHEL starting with RHEL4, in SUSE starting from 15sp2, and OpenSUSE has it disabled as well. 1) /dev/kmem was popular for rootkits [2] before it got disabled basically everywhere. Ubuntu documents [3] "There is no modern user of /dev/kmem any more beyond attackers using it to load kernel rootkits.". RHEL documents in a BZ [5] "it served no practical purpose other than to serve as a potential security problem or to enable binary module drivers to access structures/functions they shouldn't be touching" 2) /proc/kcore is a decent interface to have a controlled way to read kernel memory for debugging puposes. (will need some extensions to deal with memory offlining/unplug, memory ballooning, and poisoned pages, though) 3) It might be useful for corner case debugging [1]. KDB/KGDB might be a better fit, especially, to write random memory; harder to shoot yourself into the foot. 4) "Kernel Memory Editor" [4] hasn't seen any updates since 2000 and seems to be incompatible with 64bit [1]. For educational purposes, /proc/kcore might be used to monitor value updates -- or older kernels can be used. 5) It's broken on arm64, and therefore, completely disabled there. Looks like it's essentially unused and has been replaced by better suited interfaces for individual tasks (/proc/kcore, KDB/KGDB). Let's just remove it. [1] https://lwn.net/Articles/147901/ [2] https://www.linuxjournal.com/article/10505 [3] https://wiki.ubuntu.com/Security/Features#A.2Fdev.2Fkmem_disabled [4] https://sourceforge.net/projects/kme/ [5] https://bugzilla.redhat.com/show_bug.cgi?id=154796 Link: https://lkml.kernel.org/r/20210324102351.6932-1-david@redhat.com Link: https://lkml.kernel.org/r/20210324102351.6932-2-david@redhat.com Signed-off-by: David Hildenbrand Acked-by: Michal Hocko Acked-by: Kees Cook Cc: Linus Torvalds Cc: Greg Kroah-Hartman Cc: "Alexander A. Klimov" Cc: Alexander Viro Cc: Alexandre Belloni Cc: Andrew Lunn Cc: Andrey Zhizhikin Cc: Arnd Bergmann Cc: Benjamin Herrenschmidt Cc: Brian Cain Cc: Christian Borntraeger Cc: Christophe Leroy Cc: Chris Zankel Cc: Corentin Labbe Cc: "David S. Miller" Cc: "Eric W. Biederman" Cc: Geert Uytterhoeven Cc: Gerald Schaefer Cc: Greentime Hu Cc: Gregory Clement Cc: Heiko Carstens Cc: Helge Deller Cc: Hillf Danton Cc: huang ying Cc: Ingo Molnar Cc: Ivan Kokshaysky Cc: "James E.J. Bottomley" Cc: James Troup Cc: Jiaxun Yang Cc: Jonas Bonn Cc: Jonathan Corbet Cc: Kairui Song Cc: Krzysztof Kozlowski Cc: Kuninori Morimoto Cc: Liviu Dudau Cc: Lorenzo Pieralisi Cc: Luc Van Oostenryck Cc: Luis Chamberlain Cc: Matthew Wilcox Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Mike Rapoport Cc: Mikulas Patocka Cc: Minchan Kim Cc: Niklas Schnelle Cc: Oleksiy Avramchenko Cc: openrisc@lists.librecores.org Cc: Palmer Dabbelt Cc: Paul Mackerras Cc: "Pavel Machek (CIP)" Cc: Pavel Machek Cc: "Peter Zijlstra (Intel)" Cc: Pierre Morel Cc: Randy Dunlap Cc: Richard Henderson Cc: Rich Felker Cc: Robert Richter Cc: Rob Herring Cc: Russell King Cc: Sam Ravnborg Cc: Sebastian Andrzej Siewior Cc: Sebastian Hesselbarth Cc: sparclinux@vger.kernel.org Cc: Stafford Horne Cc: Stefan Kristiansson Cc: Steven Rostedt Cc: Sudeep Holla Cc: Theodore Dubois Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Viresh Kumar Cc: William Cohen Cc: Xiaoming Ni Cc: Yoshinori Sato Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

arch: xtensa: Remove CONFIG_OPROFILE support

2021-01-29T04:35:51Z

The "oprofile" user-space tools don't use the kernel OPROFILE support any more, and haven't in a long time. User-space has been converted to the perf interfaces. Remove the old oprofile's architecture specific support. Suggested-by: Christoph Hellwig Suggested-by: Linus Torvalds Signed-off-by: Viresh Kumar Acked-by: Robert Richter Acked-by: Max Filippov Acked-by: William Cohen Acked-by: Al Viro Acked-by: Thomas Gleixner

xtensa: reorganize vectors placement

2020-02-05T05:57:02Z

Allow vectors to be either merged into the kernel .text or put at a fixed virtual address independently of XIP option. Drop option that puts vectors at a fixed offset from the kernel text. Add choice to Kconfig. Vectors at fixed virtual address may be useful for XIP-aware MTD support and for noMMU configurations with available IRAM. Configurations without VECBASE register must put their vectors at specific locations regardless of the selected option. All other configurations should happily use merged vectors. Signed-off-by: Max Filippov

xtensa: configs: Cleanup old Kconfig IO scheduler options

2020-01-30T23:55:51Z

CONFIG_IOSCHED_DEADLINE and CONFIG_IOSCHED_CFQ are gone since commit f382fb0bcef4 ("block: remove legacy IO schedulers"). The IOSCHED_DEADLINE was replaced by MQ_IOSCHED_DEADLINE and it will be now enabled by default (along with MQ_IOSCHED_KYBER). Signed-off-by: Krzysztof Kozlowski Message-Id: <20200130192129.2677-1-krzk@kernel.org> Signed-off-by: Max Filippov

Merge tag 'xtensa-20191201' of git://github.com/jcmvbkbc/linux-xtensa

2019-12-03T20:46:44Z

Pull Xtensa updates from Max Filippov: - add support for execute in place (XIP) kernels - improvements in inline assembly: use named arguments and "m" constraints where possible - improve stack dumping - clean up system_call code and syscall tracing - various small fixes and cleanups * tag 'xtensa-20191201' of git://github.com/jcmvbkbc/linux-xtensa: (30 commits) xtensa: clean up system_call/xtensa_rt_sigreturn interaction xtensa: fix system_call interaction with ptrace xtensa: rearrange syscall tracing xtensa: fix syscall_set_return_value xtensa: drop unneeded headers from coprocessor.S xtensa: entry: Remove unneeded need_resched() loop xtensa: use MEMBLOCK_ALLOC_ANYWHERE for KASAN shadow map xtensa: fix TLB sanity checker xtensa: get rid of __ARCH_USE_5LEVEL_HACK xtensa: mm: fix PMD folding implementation xtensa: make stack dump size configurable xtensa: improve stack dumping xtensa: use "m" constraint instead of "r" in futex.h assembly xtensa: use "m" constraint instead of "a" in cmpxchg.h assembly xtensa: use named assembly arguments in cmpxchg.h xtensa: use "m" constraint instead of "a" in atomic.h assembly xtensa: use named assembly arguments in atomic.h xtensa: use "m" constraint instead of "a" in bitops.h assembly xtensa: use named assembly arguments in bitops.h xtensa: use macros to generate *_bit and test_and_*_bit functions ...

xtensa: add XIP kernel support

2019-11-26T19:33:38Z

XIP (eXecute In Place) kernel image is the image that can be run directly from ROM, using RAM only for writable data. XIP xtensa kernel differs from regular xtensa kernel in the following ways: - it has exception/IRQ vectors merged into text section. No vectors relocation takes place at kernel startup. - .data/.bss location must be specified in the kernel configuration, its content is copied there in the _startup function. - .init.text is merged with the rest of text and is executed from ROM. - when MMU is used the virtual address where the kernel will be mapped must be specified in the kernel configuration. It may be in the KSEG or in the KIO, __pa macro is adjusted to be able to handle both. Signed-off-by: Max Filippov

sysctl: Remove the sysctl system call

2019-11-26T19:03:56Z

This system call has been deprecated almost since it was introduced, and in a survey of the linux distributions I can no longer find any of them that enable CONFIG_SYSCTL_SYSCALL. The only indication that I can find that anyone might care is that a few of the defconfigs in the kernel enable CONFIG_SYSCTL_SYSCALL. However this appears in only 31 of 414 defconfigs in the kernel, so I suspect this symbols presence is simply because it is harmless to include rather than because it is necessary. As there appear to be no users of the sysctl system call, remove the code. As this removes one of the few uses of the internal kernel mount of proc I hope this allows for even more simplifications of the proc filesystem. Cc: Alex Smith Cc: Anders Berg Cc: Apelete Seketeli Cc: Arnd Bergmann Cc: Chee Nouk Phoon Cc: Chris Zankel Cc: Christian Ruppert Cc: Greg Ungerer Cc: Harvey Hunt Cc: Helge Deller Cc: Hongliang Tao Cc: Hua Yan Cc: Huacai Chen Cc: John Crispin Cc: Jonas Jensen Cc: Josh Boyer Cc: Jun Nie Cc: Kevin Hilman Cc: Kevin Wells Cc: Kumar Gala Cc: Lars-Peter Clausen Cc: Ley Foon Tan Cc: Linus Walleij Cc: Markos Chandras Cc: Max Filippov Cc: Noam Camus Cc: Olof Johansson Cc: Paul Burton Cc: Paul Mundt Cc: Phil Edworthy Cc: Pierrick Hascoet Cc: Ralf Baechle Cc: Roland Stigge Cc: Santosh Shilimkar Cc: Scott Telford Cc: Stephen Boyd Cc: Steven J. Hill Cc: Tanmay Inamdar Cc: Vineet Gupta Cc: Wolfram Sang Acked-by: Andi Kleen Reviewed-by: Kees Cook Signed-off-by: "Eric W. Biederman"

xtensa: virt: add defconfig and DTS

2019-07-08T21:32:06Z

Add defconfig and DTS for a virt board. Defconfig enables PCIe host and a number of virtio devices. DTS routes legacy PCI IRQs to the first four level-triggered external IRQ lines. CPU core with edge-triggered IRQs among the first four may need a custom DTS to work correctly. Signed-off-by: Max Filippov