summaryrefslogtreecommitdiffstats
path: root/arch/mips/math-emu/dsemul.c (follow)
Commit message (Collapse)AuthorAgeFilesLines
* MIPS: math-emu: Write-protect delay slot emulation pagesPaul Burton2018-12-201-18/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mapping the delay slot emulation page as both writeable & executable presents a security risk, in that if an exploit can write to & jump into the page then it can be used as an easy way to execute arbitrary code. Prevent this by mapping the page read-only for userland, and using access_process_vm() with the FOLL_FORCE flag to write to it from mips_dsemul(). This will likely be less efficient due to copy_to_user_page() performing cache maintenance on a whole page, rather than a single line as in the previous use of flush_cache_sigtramp(). However this delay slot emulation code ought not to be running in any performance critical paths anyway so this isn't really a problem, and we can probably do better in copy_to_user_page() anyway in future. A major advantage of this approach is that the fix is small & simple to backport to stable kernels. Reported-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Paul Burton <paul.burton@mips.com> Fixes: 432c6bacbd0c ("MIPS: Use per-mm page to execute branch delay slot instructions") Cc: stable@vger.kernel.org # v4.8+ Cc: linux-mips@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: Rich Felker <dalias@libc.org> Cc: David Daney <david.daney@cavium.com>
* License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sched/headers: Prepare to move the task_lock()/unlock() APIs to ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | <linux/sched/task.h> But first update the code that uses these facilities with the new header. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sched/headers: Prepare to remove the <linux/mm_types.h> dependency from ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | <linux/sched.h> Update code that relied on sched.h including various MM types for them. This will allow us to remove the <linux/mm_types.h> include from <linux/sched.h>. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds2016-12-241-1/+1
| | | | | | | | | | | | | This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* MIPS: Fix delay slot emulation count in debugfsPaul Burton2016-09-251-0/+1
| | | | | | | | | | | | | | | Commit 432c6bacbd0c ("MIPS: Use per-mm page to execute branch delay slot instructions") accidentally removed use of the MIPS_FPU_EMU_INC_STATS macro from do_dsemulret, leading to the ds_emul file in debugfs always returning zero even though we perform delay slot emulations. Fix this by re-adding the use of the MIPS_FPU_EMU_INC_STATS macro. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Fixes: 432c6bacbd0c ("MIPS: Use per-mm page to execute branch delay slot instructions") Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/14301/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Use per-mm page to execute branch delay slot instructionsPaul Burton2016-08-021-110/+223
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In some cases the kernel needs to execute an instruction from the delay slot of an emulated branch instruction. These cases include: - Emulated floating point branch instructions (bc1[ft]l?) for systems which don't include an FPU, or upon which the kernel is run with the "nofpu" parameter. - MIPSr6 systems running binaries targeting older revisions of the architecture, which may include branch instructions whose encodings are no longer valid in MIPSr6. Executing instructions from such delay slots is done by writing the instruction to memory followed by a trap, as part of an "emuframe", and executing it. This avoids the requirement of an emulator for the entire MIPS instruction set. Prior to this patch such emuframes are written to the user stack and executed from there. This patch moves FP branch delay emuframes off of the user stack and into a per-mm page. Allocating a page per-mm leaves userland with access to only what it had access to previously, and compared to other solutions is relatively simple. When a thread requires a delay slot emulation, it is allocated a frame. A thread may only have one frame allocated at any one time, since it may only ever be executing one instruction at any one time. In order to ensure that we can free up allocated frame later, its index is recorded in struct thread_struct. In the typical case, after executing the delay slot instruction we'll execute a break instruction with the BRK_MEMU code. This traps back to the kernel & leads to a call to do_dsemulret which frees the allocated frame & moves the user PC back to the instruction that would have executed following the emulated branch. In some cases the delay slot instruction may be invalid, such as a branch, or may trigger an exception. In these cases the BRK_MEMU break instruction will not be hit. In order to ensure that frames are freed this patch introduces dsemul_thread_cleanup() and calls it to free any allocated frame upon thread exit. If the instruction generated an exception & leads to a signal being delivered to the thread, or indeed if a signal simply happens to be delivered to the thread whilst it is executing from the struct emuframe, then we need to take care to exit the frame appropriately. This is done by either rolling back the user PC to the branch or advancing it to the continuation PC prior to signal delivery, using dsemul_thread_rollback(). If this were not done then a sigreturn would return to the struct emuframe, and if that frame had meanwhile been used in response to an emulated branch instruction within the signal handler then we would execute the wrong user code. Whilst a user could theoretically place something like a compact branch to self in a delay slot and cause their thread to become stuck in an infinite loop with the frame never being deallocated, this would: - Only affect the users single process. - Be architecturally invalid since there would be a branch in the delay slot, which is forbidden. - Be extremely unlikely to happen by mistake, and provide a program with no more ability to harm the system than a simple infinite loop would. If a thread requires a delay slot emulation & no frame is available to it (ie. the process has enough other threads that all frames are currently in use) then the thread joins a waitqueue. It will sleep until a frame is freed by another thread in the process. Since we now know whether a thread has an allocated frame due to our tracking of its index, the cookie field of struct emuframe is removed as we can be more certain whether we have a valid frame. Since a thread may only ever have a single frame at any given time, the epc field of struct emuframe is also removed & the PC to continue from is instead stored in struct thread_struct. Together these changes simplify & shrink struct emuframe somewhat, allowing twice as many frames to fit into the page allocated for them. The primary benefit of this patch is that we are now free to mark the user stack non-executable where that is possible. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com> Cc: Maciej Rozycki <maciej.rozycki@imgtec.com> Cc: Faraz Shahbazker <faraz.shahbazker@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: Matthew Fortune <matthew.fortune@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13764/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: Fix typoAndrea Gelmini2016-05-281-2/+2
| | | | | | | | | Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net> Cc: macro@imgtec.com Cc: trivial@kernel.org Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13333/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: dsemul: Remove an unused bit in ADDIUPC emulationMaciej W. Rozycki2016-05-131-1/+1
| | | | | | | | | Avoid a reader's confusion, as the calculation is correct either way. Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12283/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: dsemul: Reduce `get_isa16_mode' clutterMaciej W. Rozycki2016-01-241-8/+9
| | | | | | | | Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12178/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: dsemul: Correct description of the emulation frameMaciej W. Rozycki2016-01-241-7/+2
| | | | | | | | | | | | | | | Remove irrelevant content from the description of the emulation frame in `mips_dsemul', referring to bare-metal configurations. Update the text, reflecting the change made with commit ba3049ed4086 ("MIPS: Switch FPU emulator trap to BREAK instruction."), where we switched from using an address error exception on an unaligned access to the use of a BREAK 514 instruction causing a breakpoint exception instead. Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12176/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: Correct the emulation of microMIPS ADDIUPC instructionMaciej W. Rozycki2016-01-241-2/+22
| | | | | | | | | | | | | | | Emulate the microMIPS ADDIUPC instruction directly in `mips_dsemul'. If executed in the emulation frame, this instruction produces an incorrect result, because the value of the PC there is not the same as where the instruction originated. Reshape code so as to handle all microMIPS cases together. Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12175/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: Make microMIPS branch delay slot emulation workMaciej W. Rozycki2016-01-241-4/+7
| | | | | | | | | | | | | | | | | | | | | | | Complement commit 102cedc32a6e ("MIPS: microMIPS: Floating point support.") which introduced microMIPS FPU emulation, but did not adjust the encoding of the BREAK instruction used to terminate the branch delay slot emulation frame. Consequently the execution of any such frame is indeterminate and, depending on CPU configuration, will result in random code execution or an offending program being terminated with SIGILL. This is because the regular MIPS BREAK instruction is encoded with the 0 major and the 0xd minor opcode, however in the microMIPS instruction set this major/minor opcode pair denotes an encoding reserved for the DSP ASE. Instead the microMIPS BREAK instruction is encoded with the 0 major and the 0x7 minor opcode. Use the correct BREAK encoding for microMIPS FPU emulation then. Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12174/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: dsemul: Fix ill formatting of microMIPS partMaciej W. Rozycki2016-01-241-6/+12
| | | | | | | | | | | | Correct formatting breakage introduced with commit 102cedc32a6e ("MIPS: microMIPS: Floating point support."), so that further changes to this code can be consistent. Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12173/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: Correctly handle NOP emulationMaciej W. Rozycki2016-01-241-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix an issue introduced with commit 9ab4471c9f1b ("MIPS: math-emu: Correct delay-slot exception propagation") where the emulation of a NOP instruction signals the need to terminate the emulation loop. This in turn, if the PC has not changed from the entry to the loop, will cause the kernel to terminate the program with SIGILL. Consider this program: static double div(double d) { do d /= 2.0; while (d > .5); return d; } int main(int argc, char **argv) { return div(argc); } which gets compiled to the following binary code: 00400490 <main>: 400490: 44840000 mtc1 a0,$f0 400494: 3c020040 lui v0,0x40 400498: d44207f8 ldc1 $f2,2040(v0) 40049c: 46800021 cvt.d.w $f0,$f0 4004a0: 46220002 mul.d $f0,$f0,$f2 4004a4: 4620103c c.lt.d $f2,$f0 4004a8: 4501fffd bc1t 4004a0 <main+0x10> 4004ac: 00000000 nop 4004b0: 4620000d trunc.w.d $f0,$f0 4004b4: 03e00008 jr ra 4004b8: 44020000 mfc1 v0,$f0 4004bc: 00000000 nop Where the FPU emulator is used, depending on the number of command-line arguments this code will either run to completion or terminate with SIGILL. If no arguments are specified, then BC1T will not be taken, NOP will not be emulated and code will complete successfully. If one argument is specified, then BC1T will be taken once and NOP will be emulated. At this point the entry PC value will be 0x400498 and the new PC value, set by `mips_dsemul' will be 0x4004a0, the target of BC1T. The emulation loop will terminate, but SIGILL will not be issued, because the PC has changed. The FPU emulator will be entered again and on the second execution BC1T will not be taken, NOP will not be emulated and code will complete successfully. If two or more arguments are specified, then the first execution of BC1T will proceed as above. Upon reentering the FPU emulator the emulation loop will continue to BC1T, at which point the branch will be taken and NOP emulated again. At this point however the entry PC value will be 0x4004a0, the same as the target of BC1T. This will make the emulator conclude that execution has not advanced and therefore an unsupported FPU instruction has been encountered, and SIGILL will be sent to the process. Fix the problem by extending the internal API of `mips_dsemul', making it return -1 if no delay slot emulation frame has been made, the instruction has been handled and execution of the emulation loop needs to continue as if nothing happened. Remove code from `mips_dsemul' to reproduce steps made by the emulation loop at the conclusion of each iteration, as those will be reached normally now. Adjust call sites accordingly. Document the API. Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12172/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: Remove unused handle_dsemul function declarationMarkos Chandras2015-09-031-1/+0
| | | | | | | | | | | handle_dsemul does not exist and it's not being used in the code at all so remove its declaration. The deliberate DS emulation exception is handled by the do_dsemulret C code. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/10950/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: Correct delay-slot exception propagationMaciej W. Rozycki2015-04-081-1/+1
| | | | | | | | | | | | | | | Restore EPC at the branch whose delay slot is emulated if the delay-slot instruction signals. This is so that code in `fpu_emulator_cop1Handler' does not see EPC having advanced and mistakenly successfully resume userland execution from the location at the branch target in that case. Restoring EPC guarantees an immediate exit from the emulation loop and if EPC hasn't advanced at all since entering the loop, also issuing the signal reported by the delay-slot instruction. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9701/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: Fix delay-slot emulation cache incoherencyMaciej W. Rozycki2015-04-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Correct a cache coherency regression introduced with be1664c4 [Another round of fixes for the fp emulator.] for the emulation frame used in delay-slot emulation. Two instructions are copied into the frame and as from the commit referred a cache synchronisation call is made for the second instruction aka `badinst' of the two only. The `flush_cache_sigtramp' interface is reused that guarantees that synchronisation will be made for 8 bytes or 2 instructions starting from the address requested, although if cache lines are wider then a larger area may be synchronised. Change the call to point to the first of the two instructions aka `emul' instead, removing unpredictable behaviour resulting from cache incoherency. This bug only ever manifested itself on systems implementing 4-byte cache lines, typically MIPS I systems, causing all kinds of weirdness. This is because the sequence of two instructions starting from `emul' is 8-byte aligned and for 8-byte or wider cache lines the line synchronised will span both, so the vast majority of systems have escaped unharmed. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9698/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Add FPU emulator counter for emulated delay slots.David Daney2015-04-011-1/+1
| | | | | | | | | | | Delay slot emulation in the FPU emulator is the only kernel user of an executable stack, it is also very slow. Add a counter so we can see how many of these emulations are done. Signed-off-by: David Daney <david.daney@cavium.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/8634/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: Convert debug printks to pr_debug getting.Ralf Baechle2014-05-231-6/+3
| | | | | | And another bunch of #ifdefs bite the dust. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: Remove fine example of cargo cult programming.Ralf Baechle2014-05-211-7/+0
| | | | Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: Header file weeding.Ralf Baechle2014-05-211-14/+3
| | | | Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: math-emu: Use helpers to manipulate CAUSEF_BD flag.Ralf Baechle2014-05-211-1/+1
| | | | Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: microMIPS: Floating point support.Leonid Yegoshin2013-05-091-6/+24
| | | | | | | Add logic needed to do floating point emulation in microMIPS mode. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Steven J. Hill <Steven. Hill@imgtec.com>
* Disintegrate asm/system.h for MIPSDavid Howells2012-03-281-1/+0
| | | | | | | | Disintegrate asm/system.h for MIPS. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> cc: linux-mips@linux-mips.org
* Fix common misspellingsLucas De Marchi2011-03-311-1/+1
| | | | | | Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
* MIPS: Collect FPU emulator statistics per-CPU.David Daney2009-12-171-2/+2
| | | | | | | | | | | | | | | | | | | On SMP systems, the collection of statistics can cause cache line bouncing in the lines associated with the counters. Also there are races incrementing the counters on multiple CPUs. To fix both problems, we collect the statistics in per-CPU variables, and add them up in the debugfs read operation. As a test I ran the LTP float_bessel test on a 12 CPU Octeon system. Without CONFIG_DEBUG_FS : 2602 seconds. With CONFIG_DEBUG_FS: 2640 seconds. With non-cpu-local atomic statistics: 14569 seconds. Signed-off-by: David Daney <ddaney@caviumnetworks.com> Cc: linux-mips@linux-mips.org Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Switch FPU emulator trap to BREAK instruction.Ralf Baechle2008-10-301-4/+3
| | | | | | | | | | | | Arguably using the address error handler has always been ugly. But with processors that handle unaligned loads and stores in hardware the current mechanism ceases to work so switch it to a BREAK instruction and allocate break code 514 to the FPU emulator. Yoichi Yuasa provided a build fix for CONFIG_BUG=n. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
* [MIPS] Add some __user tagsAtsushi Nemoto2007-07-131-6/+6
| | | | | Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* header cleaning: don't include smp_lock.h when not usedRandy Dunlap2007-05-081-1/+0
| | | | | | | | | | | | Remove includes of <linux/smp_lock.h> where it is not used/needed. Suggested by Al Viro. Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc, sparc64, and arm (all 59 defconfigs). Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Now that a struct is the only member left in structRalf Baechle2005-10-291-2/+2
| | | | | | mips_fpu_emulator_stats cleanup that unnecessary nesting of structs. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* Gross macro abuse. Get rid of gpreg_t, vaddr_t, REG_TO_VA andRalf Baechle2005-10-291-5/+5
| | | | | | | | VA_TO_REG. Who ever wrote this apparently did enjoy the C Puzzle Book. ISBN 0201604612, a little old but still fun reading for the next blackout ;) Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* Cleanup fpuemuprivate declarations.Ralf Baechle2005-10-291-3/+0
| | | | Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-171-0/+172
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!