kernel/linux.git/arch/alpha/include/asm/thread_info.h, branch v6.19.11

alpha: Replace ASSEMBLY with ASSEMBLER in the alpha headers

2025-12-08T22:10:30+00:00

While the GCC and Clang compilers already define __ASSEMBLER__ automatically when compiling assembly code, __ASSEMBLY__ is a macro that only gets defined by the Makefiles in the kernel. This can be very confusing when switching between userspace and kernelspace coding, or when dealing with uapi headers that rather should use __ASSEMBLER__ instead. So let's standardize now on the __ASSEMBLER__ macro that is provided by the compilers. This is a completely mechanical patch (done with a simple "sed -i" statement). Cc: Richard Henderson Cc: Matt Turner Cc: linux-alpha@vger.kernel.org Signed-off-by: Thomas Huth Reviewed-by: Magnus Lindholm Link: https://lore.kernel.org/r/20251121100044.282684-2-thuth@redhat.com Signed-off-by: Magnus Lindholm

alpha: lazy FPU switching

2023-02-25T04:14:22+00:00

On each context switch we save the FPU registers on stack of old process and restore FPU registers from the stack of new one. That allows us to avoid doing that each time we enter/leave the kernel mode; however, that can get suboptimal in some cases. For one thing, we don't need to bother saving anything for kernel threads. For another, if between entering and leaving the kernel a thread gives CPU up more than once, it will do useless work, saving the same values every time, only to discard the saved copy as soon as it returns from switch_to(). Alternative solution: * move the array we save into from switch_stack to thread_info * have a (thread-synchronous) flag set when we save them * have another flag set when they should be restored on return to userland. * do *NOT* save/restore them in do_switch_stack()/undo_switch_stack(). * restore on the exit to user mode if the restore flag had been set. Clear both flags. * on context switch, entry to fork/clone/vfork, before entry into do_signal() and on entry into straced syscall save the registers and set the 'saved' flag unless it had been already set. * on context switch set the 'restore' flag as well. * have copy_thread() set both flags for child, so the registers would be restored once the child returns to userland. * use the saved data in setup_sigcontext(); have restore_sigcontext() set both flags and copy from sigframe to save area. * teach ptrace to look for FPU registers in thread_info instead of switch_stack. * teach isolated accesses to FPU registers (rdfpcr, wrfpcr, etc.) to check the 'saved' flag (under preempt_disable()) and work with the save area if it's been set; if 'saved' flag is found upon write access, set 'restore' flag as well. Signed-off-by: Al Viro Signed-off-by: Matt Turner

alpha: Implement "current_stack_pointer"

2023-02-14T17:36:22+00:00

To follow the existing per-arch conventions replace open-coded use of asm "$30" as "current_stack_pointer". This will let it be used in non-arch places (like HARDENED_USERCOPY). Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Cc: Geert Uytterhoeven Cc: Andrew Morton Cc: Mike Rapoport Cc: Mark Rutland Cc: "Peter Zijlstra (Intel)" Cc: Kefeng Wang Cc: "Alexander A. Klimov" Cc: linux-alpha@vger.kernel.org Signed-off-by: Kees Cook Signed-off-by: Matt Turner

alpha: _TIF_ALLWORK_MASK is unused

2022-10-30T03:31:14+00:00

... and never had been used, actually Signed-off-by: Al Viro

alpha: fix TIF_NOTIFY_SIGNAL handling

2022-10-30T03:31:14+00:00

it needs to be added to _TIF_WORK_MASK, or we might not reach do_work_pending() in the first place... Fixes: 5a9a8897c253a "alpha: add support for TIF_NOTIFY_SIGNAL" Signed-off-by: Al Viro

uaccess: remove CONFIG_SET_FS

2022-02-25T08:36:06+00:00

There are no remaining callers of set_fs(), so CONFIG_SET_FS can be removed globally, along with the thread_info field and any references to it. This turns access_ok() into a cheaper check against TASK_SIZE_MAX. As CONFIG_SET_FS is now gone, drop all remaining references to set_fs()/get_fs(), mm_segment_t, user_addr_max() and uaccess_kernel(). Acked-by: Sam Ravnborg # for sparc32 changes Acked-by: "Eric W. Biederman" Tested-by: Sergey Matyukevich # for arc changes Acked-by: Stafford Horne # [openrisc, asm-generic] Acked-by: Dinh Nguyen Signed-off-by: Arnd Bergmann

alpha: add support for TIF_NOTIFY_SIGNAL

2020-12-12T16:16:34+00:00

Wire up TIF_NOTIFY_SIGNAL handling for alpha. Cc: linux-alpha@vger.kernel.org Signed-off-by: Jens Axboe

Construct init thread stack in the linker script rather than by union

2018-01-09T23:21:02+00:00

Construct the init thread stack in the linker script rather than doing it by means of a union so that ia64's init_task.c can be got rid of. The following symbols are then made available from INIT_TASK_DATA() linker script macro: init_thread_union init_stack INIT_TASK_DATA() also expands the region to THREAD_SIZE to accommodate the size of the init stack. init_thread_union is given its own section so that it can be placed into the stack space in the right order. I'm assuming that the ia64 ordering is correct and that the task_struct is first and the thread_info second. Signed-off-by: David Howells Tested-by: Tony Luck Tested-by: Will Deacon (arm64) Tested-by: Palmer Dabbelt Acked-by: Thomas Gleixner

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

signal: consolidate {TS,TLF}_RESTORE_SIGMASK code

2016-08-02T23:35:23+00:00

In general, there's no need for the "restore sigmask" flag to live in ti->flags. alpha, ia64, microblaze, powerpc, sh, sparc (64-bit only), tile, and x86 use essentially identical alternative implementations, placing the flag in ti->status. Replace those optimized implementations with an equally good common implementation that stores it in a bitfield in struct task_struct and drop the custom implementations. Additional architectures can opt in by removing their TIF_RESTORE_SIGMASK defines. Link: http://lkml.kernel.org/r/8a14321d64a28e40adfddc90e18a96c086a6d6f9.1468522723.git.luto@kernel.org Signed-off-by: Andy Lutomirski Tested-by: Michael Ellerman [powerpc] Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Cc: Tony Luck Cc: Fenghua Yu Cc: Michal Simek Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Yoshinori Sato Cc: Rich Felker Cc: "David S. Miller" Cc: Chris Metcalf Cc: Peter Zijlstra Cc: Borislav Petkov Cc: Brian Gerst Cc: Dmitry Safonov Cc: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds