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2022-09-12MIPS: Fix comment typoJason Wang1-1/+1
The double `it' is duplicated in the comment, remove one. Signed-off-by: Jason Wang <wangborong@cdjrlc.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2022-07-11MIPS: math-emu: Use the bitmap API to allocate bitmapsChristophe JAILLET1-6/+3
Use bitmap_zalloc()/bitmap_free() instead of hand-writing them. It is less verbose and it improves the semantic. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-05-07MIPS: Use fallthrough for arch/mipsLiangliang Huang17-55/+35
Convert the various /* fallthrough */ comments to the pseudo-keyword fallthrough; Done via script: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe@perches.com/ Signed-off-by: Liangliang Huang <huangll@lemote.com> Reviewed-by: Huacai Chen <chenhc@lemote.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-01-23MIPS: Add MAC2008 SupportJiaxun Yang5-43/+118
MAC2008 means the processor implemented IEEE754 style Fused MADD instruction. It was introduced in Release3 but removed in Release5. The toolchain support of MAC2008 have never landed except for Loongson processors. This patch aimed to disabled the MAC2008 if it's optional. For MAC2008 only processors, we corrected math-emu behavior to align with actual hardware behavior. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> [paulburton@kernel.org: Fixup MIPSr2-r5 check in cpu_set_fpu_2008.] Signed-off-by: Paul Burton <paulburton@kernel.org> Cc: linux-mips@vger.kernel.org Cc: chenhc@lemote.com Cc: paul.burton@mips.com Cc: linux-kernel@vger.kernel.org
2019-11-11MIPS: math-emu: Reuse name array in debugfs_fpuemu()Paul Burton1-2/+1
The FPU_STAT_CREATE_EX() macro used 114 times in debugfs_fpuemu() declares a 32 byte char array to hold the name of a debugfs file. Since each use of the macro declares a new char array out of the scope of all the other uses, we end up with an unnecessarily large stack frame of 3648 bytes (ie. 114*32) plus the size of 2 pointers (fpuemu_debugfs_base_dir & fpuemu_debugfs_inst_dir). This is enough to trigger the frame size warnings from GCC in common configurations. Avoid the unnecessary stack bloat by using a single name char array which each usage of FPU_STAT_CREATE_EX() will reinitialize via the strcpy() in adjust_instruction_counter_name(). Signed-off-by: Paul Burton <paulburton@kernel.org> Reported-by: kbuild test robot <lkp@intel.com> URL: https://lore.kernel.org/linux-mips/201911090929.xvXYuHUz%25lkp@intel.com/
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 454Thomas Gleixner8-32/+8
Based on 1 normalized pattern(s): this program is free software you can distribute it and or modify it under the terms of the gnu general public license as published by the free software foundation version 2 of the license extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 8 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Enrico Weigelt <info@metux.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081201.231815901@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 397Thomas Gleixner33-430/+33
Based on 1 normalized pattern(s): this program is free software you can distribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin st fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 33 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531081038.563233189@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 309Thomas Gleixner2-24/+2
Based on 2 normalized pattern(s): it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program this program is free software you can redistribute it and or modify it under the terms and conditions of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 11 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000434.249870634@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22mips: math-emu: no need to check return value of debugfs_create functionsGreg Kroah-Hartman1-19/+4
When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@mips.com> Cc: James Hogan <jhogan@kernel.org> Cc: Yangtao Li <tiny.windzz@gmail.com> Cc: linux-mips@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paul Burton <paul.burton@mips.com>
2019-01-04Remove 'type' argument from access_ok() functionLinus Torvalds1-8/+8
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-20MIPS: math-emu: Write-protect delay slot emulation pagesPaul Burton1-18/+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>
2018-11-09MIPS: Ensure emulated FP sets PF_USED_MATHPaul Burton1-0/+7
Emulated floating point instructions don't ensure that the PF_USED_MATH flag is set for the task. This results in a couple of inconsistencies: - ptrace will return the default initial state of FP registers rather than the values actually stored in struct thread_struct, hiding state that has been updated by emulated floating point instructions. - If a task migrates to a CPU with an FPU after having emulated floating point instructions then its floating point register state will be reset to the default ~0 bit pattern, losing state from the emulated instructions. Fix this by calling init_fp_ctx() from fpu_emulator_cop1Handler() to consistently initialize FP state if it was previously uninitialized, setting the PF_USED_MATH flag in the process. All callers of fpu_emulator_cop1Handler() either call lose_fpu(1) before it in order to save any live FPU registers to struct thread_struct, or in the case of do_cpu() already know that the task does not own an FPU so lose_fpu(1) would be a no-op. Since we know that saving FP context will be unnecessary in the case where FP context was just initialized we move this call into fpu_emulator_cop1Handler() too, providing consistency & avoiding needless duplication. Calls to own_fpu(1) are common after return from fpu_emulator_cop1Handler() too, but this would not be a no-op in the do_cpu() case so these are left as-is. A potential future improvement could be to have fpu_emulator_cop1Handler() restore FPU state automatically only if it saved it, though this may not be optimal if some callers are better off without their current calls to own_fpu(1). One potential example of this could be mipsr2_decoder() which as-is could end up saving & restoring FP context repeatedly & unnecessarily if emulating multiple FP instructions. Signed-off-by: Paul Burton <paul.burton@mips.com> Patchwork: https://patchwork.linux-mips.org/patch/21003/ Cc: linux-mips@linux-mips.org
2018-11-05MIPS: math-emu: Change to use DEFINE_SHOW_ATTRIBUTE macroYangtao Li1-11/+1
Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code. Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> Signed-off-by: Paul Burton <paul.burton@mips.com> Patchwork: https://patchwork.linux-mips.org/patch/20988/ Cc: ralf@linux-mips.org Cc: jhogan@kernel.org Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
2017-12-12MIPS: math-emu: Mark fall throughs in switch statements with a commentAleksandar Markovic17-16/+38
Mark intentional fall throughs in switch statements with a consistent comment. In most of the cases, a new comment line containing text "fall through" is inserted. In some of the cases, existing comment contained a variation of the text "fall through" (for example, "FALL THROUGH" or "drop through"). In such cases, the existing comment is modified to contain "fall through". Lastly, in two cases, code segments were described in comments as "fall througs", but were in reality "breaks out" of switch statement. In such cases, existing comments are accordingly modified. Apart from making code easier to follow and debug, this change enables some static code analysers to interpret newly inserted comments as their annotations (and, therefore, not issue warnings of type "fall through in switch statement", which is desireable, since marked fallthroughs are intentional). Signed-off-by: Aleksandar Markovic <aleksandar.markovic@mips.com> Cc: Douglas Leung <douglas.leung@mips.com> Cc: Goran Ferenc <goran.ferenc@mips.com> Cc: James Hogan <james.hogan@mips.com> Cc: Maciej W. Rozycki <macro@mips.com> Cc: Manuel Lauss <manuel.lauss@gmail.com> Cc: Miodrag Dinic <miodrag.dinic@mips.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Petar Jovanovic <petar.jovanovic@mips.com> Cc: Raghu Gandham <raghu.gandham@mips.com> Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17588/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-12-12MIPS: math-emu: Avoid multiple assignmentAleksandar Markovic3-4/+8
Replace several instances of multiple assignment with individual assignments. Signed-off-by: Aleksandar Markovic <aleksandar.markovic@mips.com> Cc: Douglas Leung <douglas.leung@mips.com> Cc: Goran Ferenc <goran.ferenc@mips.com> Cc: James Hogan <james.hogan@mips.com> Cc: Maciej W. Rozycki <macro@mips.com> Cc: Manuel Lauss <manuel.lauss@gmail.com> Cc: Miodrag Dinic <miodrag.dinic@mips.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Petar Jovanovic <petar.jovanovic@mips.com> Cc: Raghu Gandham <raghu.gandham@mips.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17587/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-12-12MIPS: math-emu: Avoid an assignment within if statement conditionAleksandar Markovic1-1/+2
Move invocation of fpu_emu() to be out of if statement condition. This makes code easier to follow and debug, and fixes a checkpatch warning. Signed-off-by: Aleksandar Markovic <aleksandar.markovic@mips.com> Cc: Douglas Leung <douglas.leung@mips.com> Cc: Goran Ferenc <goran.ferenc@mips.com> Cc: James Hogan <james.hogan@mips.com> Cc: Maciej W. Rozycki <macro@mips.com> Cc: Miodrag Dinic <miodrag.dinic@mips.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Petar Jovanovic <petar.jovanovic@mips.com> Cc: Raghu Gandham <raghu.gandham@mips.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17586/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-12-12MIPS: math-emu: Declare function srl128() as staticAleksandar Markovic1-1/+1
Declare function srl128() as static, since it it used just locally to the source file. This also removes a sparse warning for corresponding file. Signed-off-by: Aleksandar Markovic <aleksandar.markovic@mips.com> Cc: Douglas Leung <douglas.leung@mips.com> Cc: Goran Ferenc <goran.ferenc@mips.com> Cc: James Hogan <james.hogan@mips.com> Cc: Miodrag Dinic <miodrag.dinic@mips.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Petar Jovanovic <petar.jovanovic@mips.com> Cc: Raghu Gandham <raghu.gandham@mips.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17585/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-12-12MIPS: math-emu: Avoid definition duplication for macro DPXMULT()Aleksandar Markovic3-6/+3
Avoid duplicate definition of macro DPXMULT(). Move its definition to a header. Signed-off-by: Aleksandar Markovic <aleksandar.markovic@mips.com> Cc: Douglas Leung <douglas.leung@mips.com> Cc: Goran Ferenc <goran.ferenc@mips.com> Cc: James Hogan <james.hogan@mips.com> Cc: Miodrag Dinic <miodrag.dinic@mips.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Petar Jovanovic <petar.jovanovic@mips.com> Cc: Raghu Gandham <raghu.gandham@mips.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17584/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-12-12MIPS: math-emu: Remove an unnecessary header inclusionAleksandar Markovic1-1/+0
Remove an unnecessary header inclusion of "ieee754dp.h". Signed-off-by: Aleksandar Markovic <aleksandar.markovic@mips.com> Cc: Douglas Leung <douglas.leung@mips.com> Cc: Goran Ferenc <goran.ferenc@mips.com> Cc: James Hogan <james.hogan@mips.com> Cc: Miodrag Dinic <miodrag.dinic@mips.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Petar Jovanovic <petar.jovanovic@mips.com> Cc: Raghu Gandham <raghu.gandham@mips.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17583/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-11-15Merge tag 'mips_4.15' of ↵Linus Torvalds12-56/+59
git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips Pull MIPS updates from James Hogan: "These are the main MIPS changes for 4.15. Fixes: - ralink: Fix MT7620 PCI build issues (4.5) - Disable cmpxchg64() and HAVE_VIRT_CPU_ACCOUNTING_GEN for 32-bit SMP (4.1) - Fix MIPS64 FP save/restore on 32-bit kernels (4.0) - ptrace: Pick up ptrace/seccomp changed syscall numbers (3.19) - ralink: Fix MT7628 pinmux (3.19) - BCM47XX: Fix LED inversion on WRT54GSv1 (3.17) - Fix n32 core dumping as o32 since regset support (3.13) - ralink: Drop obsolete USB_ARCH_HAS_HCD select Build system: - Default to "generic" (multiplatform) system type instead of IP22 - Use generic little endian MIPS32 r2 configuration as default defconfig instead of ip22_defconfig FPU emulation: - Fix exception generation for certain R6 FPU instructions SMP: - Allow __cpu_number_map to be larger than NR_CPUS for sparse CPU id spaces Miscellaneous: - Add iomem resource for kernel bss section for kexec/kdump - Atomics: Nudge writes on bit unlock - DT files: Standardise "ok" -> "okay" Minor cleanups: - Define virt_to_pfn() - Make thread_saved_pc static - Simplify 32-bit sign extension in __read_64bit_c0_split() - DMA: Use vma_pages() helper - FPU emulation: Replace unsigned with unsigned int - MM: Removed unused lastpfn - Alchemy: Make clk_ops const - Lasat: Use setup_timer() helper - ralink: Use BIT() in MT7620 PCI driver Platform support: BMIPS: - Enable HARDIRQS_SW_RESEND Broadcom BCM63XX: - Add clkdev lookup support - Update clk driver, UART driver, DTs to handle named refclk from DTs - Split apart various clocks to more closely match hardware - Add ethernet clocks Cavium Octeon: - Remove usage of cvmx_wait() in favour of __delay() ImgTec Pistachio: - DT: Drop deprecated dwmmc num-slots property Ingenic JZ4780: - Add NFS root to Ci20 defconfig - Add watchdog to Ci20 DT & defconfig, and allow building of watchdog driver with this SoC Generic (multiplatform): - Migrate xilfpga (MIPSfpga) platform to the generic platform Lantiq xway: - Fix ASC0/ASC1 clocks" * tag 'mips_4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips: (46 commits) MIPS: Add iomem resource for kernel bss section. MIPS: cmpxchg64() and HAVE_VIRT_CPU_ACCOUNTING_GEN don't work for 32-bit SMP MIPS: BMIPS: Enable HARDIRQS_SW_RESEND MIPS: pci: Make use of the BIT() macro inside the mt7620 driver MIPS: pci: Remove KERN_WARN instance inside the mt7620 driver MIPS: pci: Remove duplicate define in mt7620 driver MIPS: ralink: Fix typo in mt7628 pinmux function MIPS: ralink: Fix MT7628 pinmux MIPS: Fix odd fp register warnings with MIPS64r2 watchdog: jz4780: Allow selection of jz4740-wdt driver MIPS/ptrace: Update syscall nr on register changes MIPS/ptrace: Pick up ptrace/seccomp changed syscalls MIPS: Fix an n32 core file generation regset support regression MIPS: Fix MIPS64 FP save/restore on 32-bit kernels MIPS: page.h: Define virt_to_pfn() MIPS: Xilfpga: Switch to using generic defconfigs MIPS: generic: Add support for MIPSfpga MIPS: Set defconfig target to a generic system for 32r2el MIPS: Kconfig: Set default MIPS system type as generic MIPS: DTS: Remove num-slots from Pistachio SoC ...
2017-11-07MIPS: math-emu: Use preferred flavor of unsigned integer declarationsAleksandar Markovic12-42/+45
Fix occurences of unsigned integer variable declarations that are not preferred by standards of checkpatch scripts. This removes a significant number of checkpatch warnings for files in math-emu directory (several files become completely warning-free), and thus makes easier to spot (now and in the future) other, perhaps more significant, checkpatch errors and warnings. Signed-off-by: Aleksandar Markovic <aleksandar.markovic@mips.com> Reviewed-by: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Douglas Leung <douglas.leung@mips.com> Cc: Goran Ferenc <goran.ferenc@mips.com> Cc: "Maciej W. Rozycki" <macro@imgtec.com> Cc: Manuel Lauss <manuel.lauss@gmail.com> Cc: Miodrag Dinic <miodrag.dinic@mips.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Petar Jovanovic <petar.jovanovic@mips.com> Cc: Raghu Gandham <raghu.gandham@mips.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17582/ Signed-off-by: James Hogan <jhogan@kernel.org>
2017-11-07MIPS: math-emu: Fix final emulation phase for certain instructionsAleksandar Markovic1-14/+14
Fix final phase of <CLASS|MADDF|MSUBF|MAX|MIN|MAXA|MINA>.<D|S> emulation. Provide proper generation of SIGFPE signal and updating debugfs FP exception stats in cases of any exception flags set in preceding phases of emulation. CLASS.<D|S> instruction may generate "Unimplemented Operation" FP exception. <MADDF|MSUBF>.<D|S> instructions may generate "Inexact", "Unimplemented Operation", "Invalid Operation", "Overflow", and "Underflow" FP exceptions. <MAX|MIN|MAXA|MINA>.<D|S> instructions can generate "Unimplemented Operation" and "Invalid Operation" FP exceptions. The proper final processing of the cases when any FP exception flag is set is achieved by replacing "break" statement with "goto copcsr" statement. With such solution, this patch brings the final phase of emulation of the above instructions consistent with the one corresponding to the previously implemented emulation of other related FPU instructions (ADD, SUB, etc.). Fixes: 38db37ba069f ("MIPS: math-emu: Add support for the MIPS R6 CLASS FPU instruction") Fixes: e24c3bec3e8e ("MIPS: math-emu: Add support for the MIPS R6 MADDF FPU instruction") Fixes: 83d43305a1df ("MIPS: math-emu: Add support for the MIPS R6 MSUBF FPU instruction") Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction") Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction") Signed-off-by: Aleksandar Markovic <aleksandar.markovic@mips.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Douglas Leung <douglas.leung@mips.com> Cc: Goran Ferenc <goran.ferenc@mips.com> Cc: "Maciej W. Rozycki" <macro@imgtec.com> Cc: Miodrag Dinic <miodrag.dinic@mips.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Petar Jovanovic <petar.jovanovic@mips.com> Cc: Raghu Gandham <raghu.gandham@mips.com> Cc: linux-mips@linux-mips.org Cc: <stable@vger.kernel.org> # 4.3+ Patchwork: https://patchwork.linux-mips.org/patch/17581/ Signed-off-by: James Hogan <jhogan@kernel.org>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman3-0/+3
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>
2017-10-09MIPS: math-emu: Remove pr_err() calls from fpu_emu()Paul Burton1-2/+0
The FPU emulator includes 2 calls to pr_err() which are triggered by invalid instruction encodings for MIPSr6 cmp.cond.fmt instructions. These cases are not kernel errors, merely invalid instructions which are already handled by delivering a SIGILL which will provide notification that something failed in cases where that makes sense. In cases where that SIGILL is somewhat expected & being handled, for example when crashme happens to generate one of the affected bad encodings, the message is printed with no useful context about what triggered it & spams the kernel log for no good reason. Remove the pr_err() calls to make crashme run silently & treat the bad encodings the same way we do others, with a SIGILL & no further kernel log output. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Fixes: f8c3c6717a71 ("MIPS: math-emu: Add support for the CMP.condn.fmt R6 instruction") Cc: linux-mips@linux-mips.org Cc: stable <stable@vger.kernel.org> # v4.3+ Patchwork: https://patchwork.linux-mips.org/patch/17253/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: Add FP emu debugfs stats for individual instructionsAleksandar Markovic2-4/+535
Add FP emulation debugfs statistics for individual instructions. The debugfs files that contain counter values are placed in a separate directory called "instructions". This means that the default path for these new stat is "/sys/kernel/debug/mips/fpuemustats/instructions". Each instruction counter is mapped to the debugfs file that has the same name as instruction name. The lowercase is choosen as more commonly used case for instruction names. One example of usage: mips_host::/sys/kernel/debug/mips/fpuemustats/instructions # grep "" * The shortened output of this command is: abs.d:34 abs.s:5711 add.d:10401 add.s:399307 bc1eqz:3199 ... ... ... sub.s:167211 trunc.l.d:375 trunc.l.s:8054 trunc.w.d:421 trunc.w.s:27032 The limitation of this patch is that it handles R6 FP emulation instructions only. There are altogether 114 handled instructions. Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Maciej W. Rozycki <macro@imgtec.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17145/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: Add FP emu debugfs clear functionalityAleksandar Markovic1-1/+37
Add capability for the user to clear all FP emu debugfs counters. This is achieved by having a special debugfs file "fpuemustats_clear" (under default location "/sys/kernel/debug/mips"). Each access to the file results in setting all counters to zero (it is enough, let's say, to issue a "cat /sys/kernel/debug/mips/fpuemustats_clear"). This functionality already exists for R2 emulation statistics, but was missing for FP emulation statistics. The implementation in this patch is consistent with its R2 emulation counterpart. Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17144/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: Add FP emu debugfs statistics for branchesAleksandar Markovic2-0/+2
Add FP emu debugfs counter for branches. The new counter is displayed the same way as existing counter, and its default path is /sys/kernel/debug/mips/fpuemustats/. The limitation of this counter is that it counts only R6 branch instructions BC1NEZ and BC1EQZ. Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Maciej W. Rozycki <macro@imgtec.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17143/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: CLASS.D: Zero bits 32-63 of the resultAleksandar Markovic1-2/+2
Fix content of CLASS.D output bits 32-63 to match hardware behavior. Prior to this patch, bits 32-63 of CLASS.D output were not initialized, causing different 32-63 bits content of CLASS.D, based on circumstances. However, the hardware consistently returns all these bits zeroed. The documentation is not clear whether these bits should be zero or unpredictable. Since technically "all zero" case still can be viewed as belonging to "unpredictable" class of results, it is better to zero bits 32-63. Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Maciej W. Rozycki <macro@imgtec.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17142/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: RINT.<D|S>: Fix several problems by reimplementationAleksandar Markovic5-6/+187
Reimplement RINT.<D|S> kernel emulation so that all RINT.<D|S> specifications are met. For the sake of simplicity, let's analyze RINT.S only. Prior to this patch, RINT.S emulation was essentially implemented as (in pseudocode) <output> = ieee754sp_flong(ieee754sp_tlong(<input>)), where ieee754sp_tlong() and ieee754sp_flong() are functions providing conversion from double to integer, and from integer to double, respectively. On surface, this implementation looks correct, but actually fails in many cases. Following problems were detected: 1. NaN and infinity cases will not be handled properly. The function ieee754sp_flong() never returns NaN nor infinity. 2. For RINT.S, for all inputs larger than LONG_MAX, and smaller than FLT_MAX, the result will be wrong, and the overflow exception will be erroneously set. A similar problem for negative inputs exists as well. 3. For some rounding modes, for some negative inputs close to zero, the return value will be zero, and should be -zero. This is because ieee754sp_flong() never returns -zero. This patch removes the problems above by implementing dedicated functions for RINT.<D|S> emulation. The core of the new function functionality is adapted version of the core of the function ieee754sp_tlong(). However, there are many details that are implemented to match RINT.<D|S> specification. It should be said that the functionality of ieee754sp_tlong() actually closely corresponds to CVT.L.S instruction, and it is used while emulating CVT.L.S. However, RINT.S and CVT.L.S instructions differ in many aspects. This patch fulfills missing support for RINT.<D|S>. Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Cc: David S. Miller <davem@davemloft.net> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hans Verkuil <hans.verkuil@cisco.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Maciej W. Rozycki <macro@imgtec.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17141/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: CMP.Sxxx.<D|S>: Prevent occurrences of SIGILL crashesAleksandar Markovic1-0/+3
Fix CMP.Sxxx.<D|S> SIGILL crashes by fixing main switch/case statement in fpu_emul() function so that inadvertent fall-troughs are prevented. Consider, let's say, CMP.SAF.S instruction when one of inputs is zero and another input is a signaling NaN. The desired output is zero, and the exception flag "invalid operation" set. For such case, the main portion of the implementation is within "d_fmt" case of the main "switch/case" statement in fpu_emul() function. The execution will follow one of "if-else" branches that doesn't contain "goto cop1scr;" statement, and will therefore reach the end of "d_fmt" case. It will subsequently fall through to the next case, "l_fmt". After following similar pattern, the execution will fall through to the succeeding case, which is "default". The "default" case contains "return SIGILL;" statement only. This means that the caller application will crash with "illegal instruction" message. It is obvious that above described fall-throughs are unnecessary and harmful. This patch rectifies that behavior by providing "break;" statements at the end of cases "d_fmt" and "l_fmt". There are 22 instructions affected by this problem: CMP.<SAF|SEQ|SLE|SLT|SNE|SOR|SUEQ|SULE|SULT|SUN|SUNE>.<D|S>. Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Maciej W. Rozycki <macro@imgtec.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17140/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: <MADDF|MSUBF>.D: Fix accuracy (64-bit case)Douglas Leung1-39/+94
Implement fused multiply-add with correct accuracy. Fused multiply-add operation has better accuracy than respective sequential execution of multiply and add operations applied on the same inputs. This is because accuracy errors accumulate in latter case. This patch implements fused multiply-add with the same accuracy as it is implemented in hardware, using 128-bit intermediate calculations. One test case example (raw bits) that this patch fixes: MADDF.D fd,fs,ft: fd = 0x00000ca000000000 fs = ft = 0x3f40624dd2f1a9fc Fixes: e24c3bec3e8e ("MIPS: math-emu: Add support for the MIPS R6 MADDF FPU instruction") Fixes: 83d43305a1df ("MIPS: math-emu: Add support for the MIPS R6 MSUBF FPU instruction") Signed-off-by: Douglas Leung <douglas.leung@imgtec.com> Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: Bo Hu <bohu@google.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Jin Qian <jinqian@google.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: <stable@vger.kernel.org> # 4.7+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16891/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: <MADDF|MSUBF>.S: Fix accuracy (32-bit case)Douglas Leung2-70/+50
Implement fused multiply-add with correct accuracy. Fused multiply-add operation has better accuracy than respective sequential execution of multiply and add operations applied on the same inputs. This is because accuracy errors accumulate in latter case. This patch implements fused multiply-add with the same accuracy as it is implemented in hardware, using 64-bit intermediate calculations. One test case example (raw bits) that this patch fixes: MADDF.S fd,fs,ft: fd = 0x22575225 fs = ft = 0x3727c5ac Fixes: e24c3bec3e8e ("MIPS: math-emu: Add support for the MIPS R6 MADDF FPU instruction") Fixes: 83d43305a1df ("MIPS: math-emu: Add support for the MIPS R6 MSUBF FPU instruction") Signed-off-by: Douglas Leung <douglas.leung@imgtec.com> Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: Bo Hu <bohu@google.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Jin Qian <jinqian@google.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: <stable@vger.kernel.org> # 4.7+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16890/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: <MADDF|MSUBF>.<D|S>: Clean up "maddf_flags" enumerationAleksandar Markovic3-22/+20
Fix definition and usage of "maddf_flags" enumeration. Avoid duplicate definition and apply more common capitalization. This patch does not change any scenario. It just makes MADDF and MSUBF emulation code more readable and easier to maintain, and hopefully prevents future bugs as well. Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Cc: Bo Hu <bohu@google.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: Jin Qian <jinqian@google.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: <stable@vger.kernel.org> # 4.7+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16889/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: <MADDF|MSUBF>.<D|S>: Fix some cases of zero inputsAleksandar Markovic2-2/+34
Fix the cases of <MADDF|MSUBF>.<D|S> when any of two multiplicands is +0 or -0, and the third input is also +0 or -0. Depending on the signs of inputs, certain special cases must be handled. A relevant example: MADDF.S fd,fs,ft: If fs contains +0.0, ft contains -0.0, and fd contains 0.0, fd is going to contain +0.0 (without this patch, it used to contain -0.0). Fixes: e24c3bec3e8e ("MIPS: math-emu: Add support for the MIPS R6 MADDF FPU instruction") Fixes: 83d43305a1df ("MIPS: math-emu: Add support for the MIPS R6 MSUBF FPU instruction") Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Cc: Bo Hu <bohu@google.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: Jin Qian <jinqian@google.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: <stable@vger.kernel.org> # 4.7+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16888/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: <MADDF|MSUBF>.<D|S>: Fix some cases of infinite inputsAleksandar Markovic2-2/+42
Fix the cases of <MADDF|MSUBF>.<D|S> when any of two multiplicands is infinity. The correct behavior in such cases is affected by the nature of third input. Cases of addition of infinities with opposite signs and subtraction of infinities with same signs may arise and must be handles separately. Also, the value od flags argument (that determines whether the instruction is MADDF or MSUBF) affects the outcome. Relevant examples: MADDF.S fd,fs,ft: If fs contains +inf, ft contains +inf, and fd contains -inf, fd is going to contain indef (without this patch, it used to contain -inf). MSUBF.S fd,fs,ft: If fs contains +inf, ft contains 1.0, and fd contains +0.0, fd is going to contain -inf (without this patch, it used to contain +inf). Fixes: e24c3bec3e8e ("MIPS: math-emu: Add support for the MIPS R6 MADDF FPU instruction") Fixes: 83d43305a1df ("MIPS: math-emu: Add support for the MIPS R6 MSUBF FPU instruction") Signed-off-by: Douglas Leung <douglas.leung@imgtec.com> Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: Bo Hu <bohu@google.com> Cc: Jin Qian <jinqian@google.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: <stable@vger.kernel.org> # 4.7+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16887/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: <MADDF|MSUBF>.<D|S>: Fix NaN propagationAleksandar Markovic2-91/+41
Fix the cases of <MADDF|MSUBF>.<D|S> when any of three inputs is any NaN. Correct behavior of <MADDF|MSUBF>.<D|S> fd, fs, ft is following: - if any of inputs is sNaN, return a sNaN using following rules: if only one input is sNaN, return that one; if more than one input is sNaN, order of precedence for return value is fd, fs, ft - if no input is sNaN, but at least one of inputs is qNaN, return a qNaN using following rules: if only one input is qNaN, return that one; if more than one input is qNaN, order of precedence for return value is fd, fs, ft The previous code contained correct handling of some above cases, but not all. Also, such handling was scattered into various cases of "switch (CLPAIR(xc, yc))" statement, and elsewhere. With this patch, this logic is placed in one place, and "switch (CLPAIR(xc, yc))" is significantly simplified. A relevant example: MADDF.S fd,fs,ft: If fs contains qNaN1, ft contains qNaN2, and fd contains qNaN3, fd is going to contain qNaN3 (without this patch, it used to contain qNaN1). Fixes: e24c3bec3e8e ("MIPS: math-emu: Add support for the MIPS R6 MADDF FPU instruction") Fixes: 83d43305a1df ("MIPS: math-emu: Add support for the MIPS R6 MSUBF FPU instruction") Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Cc: Bo Hu <bohu@google.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: Jin Qian <jinqian@google.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: <stable@vger.kernel.org> # 4.7+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16886/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: MINA.<D|S>: Fix some cases of infinity and zero inputsAleksandar Markovic2-4/+4
Fix following special cases for MINA>.<D|S>: - if one of the inputs is zero, and the other is subnormal, normal, or infinity, the value of the former should be returned (that is, a zero). - if one of the inputs is infinity, and the other input is normal, or subnormal, the value of the latter should be returned. The previous implementation's logic for such cases was incorrect - it appears as if it implements MAXA, and not MINA instruction. A relevant example: MINA.S fd,fs,ft: If fs contains 100.0, and ft contains 0.0, fd is going to contain 0.0 (without this patch, it used to contain 100.0). Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction") Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction") Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Cc: Bo Hu <bohu@google.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: Jin Qian <jinqian@google.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: <stable@vger.kernel.org> # 4.3+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16885/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: <MAXA|MINA>.<D|S>: Fix cases of both infinite inputsAleksandar Markovic4-4/+12
Fix the value returned by <MAXA|MINA>.<D|S> fd,fs,ft, if both inputs are infinite. The previous implementation returned always the value contained in ft in such cases. The correct behavior is specified in Mips instruction set manual and is as follows: fs ft MAXA MINA --------------------------------- inf inf inf inf inf -inf inf -inf -inf inf inf -inf -inf -inf -inf -inf A relevant example: MAXA.S fd,fs,ft: If fs contains +inf, and ft contains -inf, fd is going to contain +inf (without this patch, it used to contain -inf). Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction") Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction") Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Cc: Bo Hu <bohu@google.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: Jin Qian <jinqian@google.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: <stable@vger.kernel.org> # 4.3+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16884/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: <MAXA|MINA>.<D|S>: Fix cases of input values with opposite signsAleksandar Markovic4-6/+22
Fix the value returned by <MAXA|MINA>.<D|S>, if the inputs are normal fp numbers of the same absolute value, but opposite signs. A relevant example: MAXA.S fd,fs,ft: If fs contains -3.0, and ft contains +3.0, fd is going to contain +3.0 (without this patch, it used to contain -3.0). Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction") Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction") Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Cc: Bo Hu <bohu@google.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: Jin Qian <jinqian@google.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: <stable@vger.kernel.org> # 4.3+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16883/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: <MAX|MIN>.<D|S>: Fix cases of both inputs negativeAleksandar Markovic4-32/+96
Fix the value returned by <MAX|MIN>.<D|S>, if both inputs are negative normal fp numbers. The previous logic did not take into account that if both inputs have the same sign, there should be separate treatment of the cases when both inputs are negative and when both inputs are positive. A relevant example: MAX.S fd,fs,ft: If fs contains -5.0, and ft contains -7.0, fd is going to contain -5.0 (without this patch, it used to contain -7.0). Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction") Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction") Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Cc: Bo Hu <bohu@google.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: Jin Qian <jinqian@google.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: <stable@vger.kernel.org> # 4.3+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16882/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: <MAX|MAXA|MIN|MINA>.<D|S>: Fix cases of both inputs zeroAleksandar Markovic4-24/+8
Fix the value returned by <MAX|MAXA|MIN|MINA>.<D|S>, if both inputs are zeros. The right behavior in such cases is stated in instruction reference manual and is as follows: fs ft MAX MIN MAXA MINA --------------------------------------------- 0 0 0 0 0 0 0 -0 0 -0 0 -0 -0 0 0 -0 0 -0 -0 -0 -0 -0 -0 -0 Prior to this patch, some of the above cases were yielding correct results. However, for the sake of code consistency, all such cases are rewritten in this patch. A relevant example: MAX.S fd,fs,ft: If fs contains +0.0, and ft contains -0.0, fd is going to contain +0.0 (without this patch, it used to contain -0.0). Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction") Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction") Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Cc: Bo Hu <bohu@google.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: Jin Qian <jinqian@google.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: <stable@vger.kernel.org> # 4.3+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16881/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: <MAX|MAXA|MIN|MINA>.<D|S>: Fix quiet NaN propagationAleksandar Markovic4-16/+112
Fix the value returned by <MAX|MAXA|MIN|MINA>.<D|S> fd,fs,ft, if both inputs are quiet NaNs. The <MAX|MAXA|MIN|MINA>.<D|S> specifications state that the returned value in such cases should be the quiet NaN contained in register fs. A relevant example: MAX.S fd,fs,ft: If fs contains qNaN1, and ft contains qNaN2, fd is going to contain qNaN1 (without this patch, it used to contain qNaN2). Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction") Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction") Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Cc: Bo Hu <bohu@google.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: Jin Qian <jinqian@google.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: <stable@vger.kernel.org> # 4.3+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16880/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: Correct user fault_addr typePaul Burton1-4/+4
The fault_addr argument to fpu_emulator_cop1Handler(), fpux_emu() and cop1Emulate() has up until now been declared as: void *__user *fault_addr This is essentially a pointer in user memory which points to a pointer to void. This is not the intent for our code, which is actually operating on a pointer to a pointer to void where the pointer to void is pointing at user memory. ie. the pointer is in kernel memory & points to user memory. This mismatch produces a lot of sparse warnings that look like this: arch/mips/math-emu/cp1emu.c:1485:45: warning: incorrect type in assignment (different address spaces) expected void *[noderef] <asn:1><noident> got unsigned int [noderef] [usertype] <asn:1>*[assigned] va Fix these by modifying the declaration of the fault_addr argument to: void __user **fault_addr Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: trivial@kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17173/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: math-emu: do not use bools for arithmeticManuel Lauss1-2/+2
GCC-7 complains about a boolean value being used with an arithmetic AND: arch/mips/math-emu/cp1emu.c: In function 'cop1Emulate': arch/mips/math-emu/cp1emu.c:838:14: warning: '~' on a boolean expression [-Wbool-operation] fpr = (x) & ~(cop1_64bit(xcp) == 0); \ ^ arch/mips/math-emu/cp1emu.c:1068:3: note: in expansion of macro 'DITOREG' DITOREG(dval, MIPSInst_RT(ir)); ^~~~~~~ arch/mips/math-emu/cp1emu.c:838:14: note: did you mean to use logical not? fpr = (x) & ~(cop1_64bit(xcp) == 0); \ Since cop1_64bit() returns and int, just flip the LSB. Suggested-by: Maciej W. Rozycki <macro@imgtec.com> Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com> Reviewed-by: Maciej W. Rozycki <macro@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17058/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-07-15Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds1-3/+40
Pull MIPS updates from Ralf Baechle: "Boston platform support: - Document DT bindings - Add CLK driver for board clocks CM: - Avoid per-core locking with CM3 & higher - WARN on attempt to lock invalid VP, not BUG CPS: - Select CONFIG_SYS_SUPPORTS_SCHED_SMT for MIPSr6 - Prevent multi-core with dcache aliasing - Handle cores not powering down more gracefully - Handle spurious VP starts more gracefully DSP: - Add lwx & lhx missaligned access support eBPF: - Add MIPS support along with many supporting change to add the required infrastructure Generic arch code: - Misc sysmips MIPS_ATOMIC_SET fixes - Drop duplicate HAVE_SYSCALL_TRACEPOINTS - Negate error syscall return in trace - Correct forced syscall errors - Traced negative syscalls should return -ENOSYS - Allow samples/bpf/tracex5 to access syscall arguments for sane traces - Cleanup from old Kconfig options in defconfigs - Fix PREF instruction usage by memcpy for MIPS R6 - Fix various special cases in the FPU eulation - Fix some special cases in MIPS16e2 support - Fix MIPS I ISA /proc/cpuinfo reporting - Sort MIPS Kconfig alphabetically - Fix minimum alignment requirement of IRQ stack as required by ABI / GCC - Fix special cases in the module loader - Perform post-DMA cache flushes on systems with MAARs - Probe the I6500 CPU - Cleanup cmpxchg and add support for 1 and 2 byte operations - Use queued read/write locks (qrwlock) - Use queued spinlocks (qspinlock) - Add CPU shared FTLB feature detection - Handle tlbex-tlbp race condition - Allow storing pgd in C0_CONTEXT for MIPSr6 - Use current_cpu_type() in m4kc_tlbp_war() - Support Boston in the generic kernel Generic platform: - yamon-dt: Pull YAMON DT shim code out of SEAD-3 board - yamon-dt: Support > 256MB of RAM - yamon-dt: Use serial* rather than uart* aliases - Abstract FDT fixup application - Set RTC_ALWAYS_BCD to 0 - Add a MAINTAINERS entry core kernel: - qspinlock.c: include linux/prefetch.h Loongson 3: - Add support Perf: - Add I6500 support SEAD-3: - Remove GIC timer from DT - Set interrupt-parent per-device, not at root node - Fix GIC interrupt specifiers SMP: - Skip IPI setup if we only have a single CPU VDSO: - Make comment match reality - Improvements to time code in VDSO" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (86 commits) locking/qspinlock: Include linux/prefetch.h MIPS: Fix MIPS I ISA /proc/cpuinfo reporting MIPS: Fix minimum alignment requirement of IRQ stack MIPS: generic: Support MIPS Boston development boards MIPS: DTS: img: Don't attempt to build-in all .dtb files clk: boston: Add a driver for MIPS Boston board clocks dt-bindings: Document img,boston-clock binding MIPS: Traced negative syscalls should return -ENOSYS MIPS: Correct forced syscall errors MIPS: Negate error syscall return in trace MIPS: Drop duplicate HAVE_SYSCALL_TRACEPOINTS select MIPS16e2: Provide feature overrides for non-MIPS16 systems MIPS: MIPS16e2: Report ASE presence in /proc/cpuinfo MIPS: MIPS16e2: Subdecode extended LWSP/SWSP instructions MIPS: MIPS16e2: Identify ASE presence MIPS: VDSO: Fix a mismatch between comment and preprocessor constant MIPS: VDSO: Add implementation of gettimeofday() fallback MIPS: VDSO: Add implementation of clock_gettime() fallback MIPS: VDSO: Fix conversions in do_monotonic()/do_monotonic_coarse() MIPS: Use current_cpu_type() in m4kc_tlbp_war() ...
2017-06-29MIPS: math-emu: For MFHC1/MTHC1 also return SIGILL right awayMaciej W. Rozycki1-3/+2
Update commit 1ac944007bed ("MIPS: math-emu: Add mfhc1 & mthc1 support.") and like done throughout `cop1Emulate' for other cases also for the MFHC1 and MTHC1 instructions return SIGILL right away rather than jumping to a single `return' statement. Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16401/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-06-29MIPS: math-emu: Prevent wrong ISA mode instruction emulationMaciej W. Rozycki1-0/+38
Terminate FPU emulation immediately whenever an ISA mode switch has been observed. This is so that we do not interpret machine code in the wrong mode, for example when a regular MIPS FPU instruction has been placed in a delay slot of a jump that switches into the MIPS16 mode, as with the following code (taken from a GCC test suite case): 00400650 <set_fast_math>: 400650: 3c020100 lui v0,0x100 400654: 03e00008 jr ra 400658: 44c2f800 ctc1 v0,c1_fcsr 40065c: 00000000 nop [...] 004012d0 <__libc_csu_init>: 4012d0: f000 6a02 li v0,2 4012d4: f150 0b1c la v1,3f9430 <_DYNAMIC-0x6df0> 4012d8: f400 3240 sll v0,16 4012dc: e269 addu v0,v1 4012de: 659a move gp,v0 4012e0: f00c 64f6 save a0-a2,48,ra,s0-s1 4012e4: 673c move s1,gp 4012e6: f010 9978 lw v1,-32744(s1) 4012ea: d204 sw v0,16(sp) 4012ec: eb40 jalr v1 4012ee: 653b move t9,v1 4012f0: f010 997c lw v1,-32740(s1) 4012f4: f030 9920 lw s1,-32736(s1) 4012f8: e32f subu v1,s1 4012fa: 326b sra v0,v1,2 4012fc: d206 sw v0,24(sp) 4012fe: 220c beqz v0,401318 <__libc_csu_init+0x48> 401300: 6800 li s0,0 401302: 99e0 lw a3,0(s1) 401304: 4801 addiu s0,1 401306: 960e lw a2,56(sp) 401308: 4904 addiu s1,4 40130a: 950d lw a1,52(sp) 40130c: 940c lw a0,48(sp) 40130e: ef40 jalr a3 401310: 653f move t9,a3 401312: 9206 lw v0,24(sp) 401314: ea0a cmp v0,s0 401316: 61f5 btnez 401302 <__libc_csu_init+0x32> 401318: 6476 restore 48,ra,s0-s1 40131a: e8a0 jrc ra Here `set_fast_math' is called from `40130e' (`40130f' with the ISA bit) and emulation triggers for the CTC1 instruction. As it is in a jump delay slot emulation continues from `401312' (`401313' with the ISA bit). However we have no path to handle MIPS16 FPU code emulation, because there are no MIPS16 FPU instructions. So the default emulation path is taken, interpreting a 32-bit word fetched by `get_user' from `401313' as a regular MIPS instruction, which is: 401313: f5ea0a92 sdc1 $f10,2706(t7) This makes the FPU emulator proceed with the supposed SDC1 instruction and consequently makes the program considered here terminate with SIGSEGV. A similar although less severe issue exists with pure-microMIPS processors in the case where similarly an FPU instruction is emulated in a delay slot of a register jump that (incorrectly) switches into the regular MIPS mode. A subsequent instruction fetch from the jump's target is supposed to cause an Address Error exception, however instead we proceed with regular MIPS FPU emulation. For simplicity then, always terminate the emulation loop whenever a mode change is detected, denoted by an ISA mode bit flip. As from commit 377cb1b6c16a ("MIPS: Disable MIPS16/microMIPS crap for platforms not supporting these ASEs.") the result of `get_isa16_mode' can be hardcoded to 0, so we need to examine the ISA mode bit by hand. This complements commit 102cedc32a6e ("MIPS: microMIPS: Floating point support.") which added JALX decoding to FPU emulation. Fixes: 102cedc32a6e ("MIPS: microMIPS: Floating point support.") Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # 3.9+ Patchwork: https://patchwork.linux-mips.org/patch/16393/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-06-28MIPS: math-emu: Handle zero accumulator case in MADDF and MSUBF separatelyAleksandar Markovic2-2/+8
If accumulator value is zero, just return the value of previously calculated product. This brings logic in MADDF/MSUBF implementation closer to the logic in ADD/SUB case. Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Cc: James.Hogan@imgtec.com Cc: Paul.Burton@imgtec.com Cc: Raghu.Gandham@imgtec.com Cc: Leonid.Yegoshin@imgtec.com Cc: Douglas.Leung@imgtec.com Cc: Petar.Jovanovic@imgtec.com Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16512/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-04-10MIPS: math-emu: Fix BC1EQZ and BC1NEZ condition handlingDouglas Leung1-4/+6
Correct the treatment of branching conditions for BC1EQZ and BC1NEZ instructions in function isBranchInstr(). Previously, corresponding conditions were swapped, which in turn meant that, for these two instructions, function isBranchInstr() returned wrong value in its output parameter contpc. This change is actually an extension of the fix done by the commit 93583e178ebf ("MIPS: math-emu: Fix BC1{EQ,NE}Z emulation"). That commit dealt with a similar problem in function cop1Emulate(), while this commit deals with condition handling in function isBranchInstr(). The code styles of changes in these two commits are kept as consistent as possible. Signed-off-by: Douglas Leung <douglas.leung@imgtec.com> Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Reviewed-by: Paul Burton <paul.burton@imgtec.com> Cc: james.hogan@imgtec.com Cc: leonid.yegoshin@imgtec.com Cc: petar.jovanovic@imgtec.com Cc: goran.ferenc@imgtec.com Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/15489/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-03-02sched/headers: Prepare to move the task_lock()/unlock() APIs to ↵Ingo Molnar1-0/+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>