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2017-11-07MIPS: Allow __cpu_number_map to be larger than NR_CPUSDavid Daney
In systems where the CPU id space is sparse, this allows a smaller NR_CPUS to be chosen, thus keeping internal data structures smaller. Signed-off-by: David Daney <david.daney@cavium.com> Signed-off-by: Carlos Munoz <cmunoz@caviumnetworks.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17388/ [jhogan@kernel.org: Add depends on SMP to fix "warning: symbol value '' invalid for MIPS_NR_CPU_NR_MAP"] Signed-off-by: James Hogan <jhogan@kernel.org>
2017-10-09MIPS: make thread_saved_pc staticTobias Klauser
The only user of thread_saved_pc() in non-arch-specific code was removed in commit 8243d5597793 ("sched/core: Remove pointless printout in sched_show_task()"), so it no longer needs to be globally defined for MIPS and can be made static. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17303/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-20MIPS: Fix perf event initPaul Burton
Commit c311c797998c ("cpumask: make "nr_cpumask_bits" unsigned") modified mipspmu_event_init() to cast the struct perf_event cpu field to an unsigned integer before it is compared with nr_cpumask_bits (and *ahem* did so without copying the linux-mips mailing list or any MIPS developers...). This is broken because the cpu field may be -1 for events which follow a process rather than being affine to a particular CPU. When this is the case the cast to an unsigned int results in a value equal to ULONG_MAX, which is always greater than nr_cpumask_bits so we always fail mipspmu_event_init() and return -ENODEV. The check against nr_cpumask_bits seems nonsensical anyway, so this patch simply removes it. The cpu field is going to either be -1 or a valid CPU number. Comparing it with nr_cpumask_bits is effectively checking that it's a valid cpu number, but it seems safe to rely on the core perf events code to ensure that's the case. The end result is that this fixes use of perf on MIPS when not constraining events to a particular CPU, and fixes the "perf list hw" command which fails to list any events without this. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Fixes: c311c797998c ("cpumask: make "nr_cpumask_bits" unsigned") Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-mips@linux-mips.org Cc: stable <stable@vger.kernel.org> # v4.12+ Patchwork: https://patchwork.linux-mips.org/patch/17323/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-15Merge branch '4.14-features' of ↵Linus Torvalds
git://git.linux-mips.org/pub/scm/ralf/upstream-linus Pull MIPS updates from Ralf Baechle: "This is the main pull request for 4.14 for MIPS; below a summary of the non-merge commits: CM: - Rename mips_cm_base to mips_gcr_base - Specify register size when generating accessors - Use BIT/GENMASK for register fields, order & drop shifts - Add cluster & block args to mips_cm_lock_other() CPC: - Use common CPS accessor generation macros - Use BIT/GENMASK for register fields, order & drop shifts - Introduce register modify (set/clear/change) accessors - Use change_*, set_* & clear_* where appropriate - Add CM/CPC 3.5 register definitions - Use GlobalNumber macros rather than magic numbers - Have asm/mips-cps.h include CM & CPC headers - Cluster support for topology functions - Detect CPUs in secondary clusters CPS: - Read GIC_VL_IDENT directly, not via irqchip driver DMA: - Consolidate coherent and non-coherent dma_alloc code - Don't use dma_cache_sync to implement fd_cacheflush FPU emulation / FP assist code: - Another series of 14 commits fixing corner cases such as NaN propgagation and other special input values. - Zero bits 32-63 of the result for a CLASS.D instruction. - Enhanced statics via debugfs - Do not use bools for arithmetic. GCC 7.1 moans about this. - Correct user fault_addr type Generic MIPS: - Enhancement of stack backtraces - Cleanup from non-existing options - Handle non word sized instructions when examining frame - Fix detection and decoding of ADDIUSP instruction - Fix decoding of SWSP16 instruction - Refactor handling of stack pointer in get_frame_info - Remove unreachable code from force_fcr31_sig() - Convert to using %pOF instead of full_name - Remove the R6000 support. - Move FP code from *_switch.S to *_fpu.S - Remove unused ST_OFF from r2300_switch.S - Allow platform to specify multiple its.S files - Add #includes to various files to ensure code builds reliable and without warning.. - Remove __invalidate_kernel_vmap_range - Remove plat_timer_setup - Declare various variables & functions static - Abstract CPU core & VP(E) ID access through accessor functions - Store core & VP IDs in GlobalNumber-style variable - Unify checks for sibling CPUs - Add CPU cluster number accessors - Prevent direct use of generic_defconfig - Make CONFIG_MIPS_MT_SMP default y - Add __ioread64_copy - Remove unnecessary inclusions of linux/irqchip/mips-gic.h GIC: - Introduce asm/mips-gic.h with accessor functions - Use new GIC accessor functions in mips-gic-timer - Remove counter access functions from irq-mips-gic.c - Remove gic_read_local_vp_id() from irq-mips-gic.c - Simplify shared interrupt pending/mask reads in irq-mips-gic.c - Simplify gic_local_irq_domain_map() in irq-mips-gic.c - Drop gic_(re)set_mask() functions in irq-mips-gic.c - Remove gic_set_polarity(), gic_set_trigger(), gic_set_dual_edge(), gic_map_to_pin() and gic_map_to_vpe() from irq-mips-gic.c. - Convert remaining shared reg access, local int mask access and remaining local reg access to new accessors - Move GIC_LOCAL_INT_* to asm/mips-gic.h - Remove GIC_CPU_INT* macros from irq-mips-gic.c - Move various definitions to the driver - Remove gic_get_usm_range() - Remove __gic_irq_dispatch() forward declaration - Remove gic_init() - Use mips_gic_present() in place of gic_present and remove gic_present - Move gic_get_c0_*_int() to asm/mips-gic.h - Remove linux/irqchip/mips-gic.h - Inline __gic_init() - Inline gic_basic_init() - Make pcpu_masks a per-cpu variable - Use pcpu_masks to avoid reading GIC_SH_MASK* - Clean up mti, reserved-cpu-vectors handling - Use cpumask_first_and() in gic_set_affinity() - Let the core set struct irq_common_data affinity microMIPS: - Fix microMIPS stack unwinding on big endian systems MIPS-GIC: - SYNC after enabling GIC region NUMA: - Remove the unused parent_node() macro R6: - Constify r2_decoder_tables - Add accessor & bit definitions for GlobalNumber SMP: - Constify smp ops - Allow boot_secondary SMP op to return errors VDSO: - Drop gic_get_usm_range() usage - Avoid use of linux/irqchip/mips-gic.h Platform changes: Alchemy: - Add devboard machine type to cpuinfo - update cpu feature overrides - Threaded carddetect irqs for devboards AR7: - allow NULL clock for clk_get_rate BCM63xx: - Fix ENETDMA_6345_MAXBURST_REG offset - Allow NULL clock for clk_get_rate CI20: - Enable GPIO and RTC drivers in defconfig - Add ethernet and fixed-regulator nodes to DTS Generic platform: - Move Boston and NI 169445 FIT image source to their own files - Include asm/bootinfo.h for plat_fdt_relocated() - Include asm/time.h for get_c0_*_int() - Include asm/bootinfo.h for plat_fdt_relocated() - Include asm/time.h for get_c0_*_int() - Allow filtering enabled boards by requirements - Don't explicitly disable CONFIG_USB_SUPPORT - Bump default NR_CPUS to 16 JZ4700: - Probe the jz4740-rtc driver from devicetree Lantiq: - Drop check of boot select from the spi-falcon driver. - Drop check of boot select from the lantiq-flash MTD driver. - Access boot cause register in the watchdog driver through regmap - Add device tree binding documentation for the watchdog driver - Add docs for the RCU DT bindings. - Convert the fpi bus driver to a platform_driver - Remove ltq_reset_cause() and ltq_boot_select( - Switch to a proper reset driver - Switch to a new drivers/soc GPHY driver - Add an USB PHY driver for the Lantiq SoCs using the RCU module - Use of_platform_default_populate instead of __dt_register_buses - Enable MFD_SYSCON to be able to use it for the RCU MFD - Replace ltq_boot_select() with dummy implementation. Loongson 2F: - Allow NULL clock for clk_get_rate Malta: - Use new GIC accessor functions NI 169445: - Add support for NI 169445 board. - Only include in 32r2el kernels Octeon: - Add support for watchdog of 78XX SOCs. - Add support for watchdog of CN68XX SOCs. - Expose support for mips32r1, mips32r2 and mips64r1 - Enable more drivers in config file - Add support for accessing the boot vector. - Remove old boot vector code from watchdog driver - Define watchdog registers for 70xx, 73xx, 78xx, F75xx. - Make CSR functions node aware. - Allow access to CIU3 IRQ domains. - Misc cleanups in the watchdog driver Omega2+: - New board, add support and defconfig Pistachio: - Enable Root FS on NFS in defconfig Ralink: - Add Mediatek MT7628A SoC - Allow NULL clock for clk_get_rate - Explicitly request exclusive reset control in the pci-mt7620 PCI driver. SEAD3: - Only include in 32 bit kernels by default VoCore: - Add VoCore as a vendor t0 dt-bindings - Add defconfig file" * '4.14-features' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (167 commits) MIPS: Refactor handling of stack pointer in get_frame_info MIPS: Stacktrace: Fix microMIPS stack unwinding on big endian systems MIPS: microMIPS: Fix decoding of swsp16 instruction MIPS: microMIPS: Fix decoding of addiusp instruction MIPS: microMIPS: Fix detection of addiusp instruction MIPS: Handle non word sized instructions when examining frame MIPS: ralink: allow NULL clock for clk_get_rate MIPS: Loongson 2F: allow NULL clock for clk_get_rate MIPS: BCM63XX: allow NULL clock for clk_get_rate MIPS: AR7: allow NULL clock for clk_get_rate MIPS: BCM63XX: fix ENETDMA_6345_MAXBURST_REG offset mips: Save all registers when saving the frame MIPS: Add DWARF unwinding to assembly MIPS: Make SAVE_SOME more standard MIPS: Fix issues in backtraces MIPS: jz4780: DTS: Probe the jz4740-rtc driver from devicetree MIPS: Ci20: Enable RTC driver watchdog: octeon-wdt: Add support for 78XX SOCs. watchdog: octeon-wdt: Add support for cn68XX SOCs. watchdog: octeon-wdt: File cleaning. ...
2017-09-14Merge branch 'work.set_fs' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more set_fs removal from Al Viro: "Christoph's 'use kernel_read and friends rather than open-coding set_fs()' series" * 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: unexport vfs_readv and vfs_writev fs: unexport vfs_read and vfs_write fs: unexport __vfs_read/__vfs_write lustre: switch to kernel_write gadget/f_mass_storage: stop messing with the address limit mconsole: switch to kernel_read btrfs: switch write_buf to kernel_write net/9p: switch p9_fd_read to kernel_write mm/nommu: switch do_mmap_private to kernel_read serial2002: switch serial2002_tty_write to kernel_{read/write} fs: make the buf argument to __kernel_write a void pointer fs: fix kernel_write prototype fs: fix kernel_read prototype fs: move kernel_read to fs/read_write.c fs: move kernel_write to fs/read_write.c autofs4: switch autofs4_write to __kernel_write ashmem: switch to ->read_iter
2017-09-11Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull namespace updates from Eric Biederman: "Life has been busy and I have not gotten half as much done this round as I would have liked. I delayed it so that a minor conflict resolution with the mips tree could spend a little time in linux-next before I sent this pull request. This includes two long delayed user namespace changes from Kirill Tkhai. It also includes a very useful change from Serge Hallyn that allows the security capability attribute to be used inside of user namespaces. The practical effect of this is people can now untar tarballs and install rpms in user namespaces. It had been suggested to generalize this and encode some of the namespace information information in the xattr name. Upon close inspection that makes the things that should be hard easy and the things that should be easy more expensive. Then there is my bugfix/cleanup for signal injection that removes the magic encoding of the siginfo union member from the kernel internal si_code. The mips folks reported the case where I had used FPE_FIXME me is impossible so I have remove FPE_FIXME from mips, while at the same time including a return statement in that case to keep gcc from complaining about unitialized variables. I almost finished the work to get make copy_siginfo_to_user a trivial copy to user. The code is available at: git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git neuter-copy_siginfo_to_user-v3 But I did not have time/energy to get the code posted and reviewed before the merge window opened. I was able to see that the security excuse for just copying fields that we know are initialized doesn't work in practice there are buggy initializations that don't initialize the proper fields in siginfo. So we still sometimes copy unitialized data to userspace" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: Introduce v3 namespaced file capabilities mips/signal: In force_fcr31_sig return in the impossible case signal: Remove kernel interal si_code magic fcntl: Don't use ambiguous SIG_POLL si_codes prctl: Allow local CAP_SYS_ADMIN changing exe_file security: Use user_namespace::level to avoid redundant iterations in cap_capable() userns,pidns: Verify the userns for new pid namespaces signal/testing: Don't look for __SI_FAULT in userspace signal/mips: Document a conflict with SI_USER with SIGFPE signal/sparc: Document a conflict with SI_USER with SIGFPE signal/ia64: Document a conflict with SI_USER with SIGFPE signal/alpha: Document a conflict with SI_USER for SIGTRAP
2017-09-06MIPS: Refactor handling of stack pointer in get_frame_infoMatt Redfearn
Commit 34c2f668d0f6 ("MIPS: microMIPS: Add unaligned access support.") added handling of microMIPS instructions to manipulate the stack pointer. The code that was added violates code style rules with long lines caused by lots of nested conditionals. The added code interprets (inline) any known stack pointer manipulation instruction to find the stack frame size. Handling the microMIPS cases added quite a bit of complication to this function. Refactor is_sp_move_ins to perform the interpretation of the immediate as the instruction manipulating the stack pointer is found. This reduces the amount of indentation required in get_frame_info, and more closely matches the operation of is_ra_save_ins. Suggested-by: Maciej W. Rozycki <macro@imgtec.com> Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16958/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-06MIPS: Stacktrace: Fix microMIPS stack unwinding on big endian systemsMatt Redfearn
The stack unwinding code uses the mips_instuction union to decode the instructions it finds. That union uses the __BITFIELD_FIELD macro to reorder depending on endianness. The stack unwinding code always places 16bit instructions in halfword 1 of the union. This makes the union accesses correct for little endian systems. Similarly, 32bit instructions are reordered such that they are correct for little endian systems. This handling leaves unwinding the stack on big endian systems broken, as the mips_instruction union will then look for the fields in the wrong halfword. To fix this, use a logical shift to place the 16bit instruction into the correct position in the word field of the union. Use the same shifting to order the 2 halfwords of 32bit instuctions. Then replace accesses to the halfword with accesses to the shifted word. In the case of the ADDIUS5 instruction, switch to using the mm16_r5_format union member to avoid the need for a 16bit shift. Fixes: 34c2f668d0f6 ("MIPS: microMIPS: Add unaligned access support.") Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16956/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-06MIPS: microMIPS: Fix decoding of swsp16 instructionMatt Redfearn
When the immediate encoded in the instruction is accessed, it is sign extended due to being a signed value being assigned to a signed integer. The ISA specifies that this operation is an unsigned operation. The sign extension leads us to incorrectly decode: 801e9c8e: cbf1 sw ra,68(sp) As having an immediate of 1073741809. Since the instruction format does not specify signed/unsigned, and this is currently the only location to use this instuction format, change it to an unsigned immediate. Fixes: bb9bc4689b9c ("MIPS: Calculate microMIPS ra properly when unwinding the stack") Suggested-by: Paul Burton <paul.burton@imgtec.com> Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com> Cc: Miodrag Dinic <miodrag.dinic@imgtec.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: David Daney <david.daney@cavium.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16957/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-06MIPS: microMIPS: Fix decoding of addiusp instructionMatt Redfearn
Commit 34c2f668d0f6 ("MIPS: microMIPS: Add unaligned access support.") added handling of microMIPS instructions to manipulate the stack pointer. Unfortunately the decoding of the addiusp instruction was incorrect, and performed a left shift by 2 bits to the raw immediate, rather than decoding the immediate and then performing the shift, as documented in the ISA. This led to incomplete stack traces, due to incorrect frame sizes being calculated. For example the instruction: 801faee0 <do_sys_poll>: 801faee0: 4e25 addiu sp,sp,-952 As decoded by objdump, would be interpreted by the existing code as having manipulated the stack pointer by +1096. Fix this by changing the order of decoding the immediate and applying the left shift. Also change to accessing the instuction through the union to avoid the endianness problem of accesing halfword[0], which will fail on big endian systems. Cope with the special behaviour of immediates 0x0, 0x1, 0x1fe and 0x1ff by XORing with 0x100 again if mod(immediate) < 4. This logic was tested with the following test code: int main(int argc, char **argv) { unsigned int enc; int imm; for (enc = 0; enc < 512; ++enc) { int tmp = enc << 2; imm = -(signed short)(tmp | ((tmp & 0x100) ? 0xfe00 : 0)); unsigned short tmp = enc; tmp = (tmp ^ 0x100) - 0x100; if ((unsigned short)(tmp + 2) < 4) tmp ^= 0x100; imm = -(signed short)(tmp << 2); printf("%#x\t%d\t->\t(%#x\t%d)\t%#x\t%d\n", enc, enc, (short)tmp, (short)tmp, imm, imm); } return EXIT_SUCCESS; } Which generates the table: input encoding -> tmp (matching manual) frame size ----------------------------------------------------------------------- 0 0 -> (0x100 256) 0xfffffc00 -1024 0x1 1 -> (0x101 257) 0xfffffbfc -1028 0x2 2 -> (0x2 2) 0xfffffff8 -8 0x3 3 -> (0x3 3) 0xfffffff4 -12 ... 0xfe 254 -> (0xfe 254) 0xfffffc08 -1016 0xff 255 -> (0xff 255) 0xfffffc04 -1020 0x100 256 -> (0xffffff00 -256) 0x400 1024 0x101 257 -> (0xffffff01 -255) 0x3fc 1020 ... 0x1fc 508 -> (0xfffffffc -4) 0x10 16 0x1fd 509 -> (0xfffffffd -3) 0xc 12 0x1fe 510 -> (0xfffffefe -258) 0x408 1032 0x1ff 511 -> (0xfffffeff -257) 0x404 1028 Thanks to James Hogan for the test code & verifying the logic. Fixes: 34c2f668d0f6 ("MIPS: microMIPS: Add unaligned access support.") Suggested-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16955/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-06MIPS: microMIPS: Fix detection of addiusp instructionMatt Redfearn
The addiusp instruction uses the pool16d opcode, with bit 0 of the immediate set. The test for the addiusp opcode erroneously did a logical and of the immediate with mm_addiusp_func, which has value 1, so this test always passes when the immediate is non-zero. Fix the test by replacing the logical and with a bitwise and. Fixes: 34c2f668d0f6 ("MIPS: microMIPS: Add unaligned access support.") Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16954/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-06MIPS: Handle non word sized instructions when examining frameMatt Redfearn
Commit 34c2f668d0f6b ("MIPS: microMIPS: Add unaligned access support.") added fairly broken support for handling 16bit microMIPS instructions in get_frame_info(). It adjusts the instruction pointer by 16bits in the case of a 16bit sp move instruction, but not any other 16bit instruction. Commit b6c7a324df37 ("MIPS: Fix get_frame_info() handling of microMIPS function size") goes some way to fixing get_frame_info() to iterate over microMIPS instuctions, but the instruction pointer is still manipulated using a postincrement, and is of union mips_instruction type. Since the union is sized to the largest member (a word), but microMIPS instructions are a mix of halfword and word sizes, the function does not always iterate correctly, ending up misaligned with the instruction stream and interpreting it incorrectly. Since the instruction modifying the stack pointer is usually the first in the function, that one is usually handled correctly. But the instruction which saves the return address to the sp is some variable number of instructions into the frame and is frequently missed due to not being on a word boundary, leading to incomplete walking of the stack. Fix this by incrementing the instruction pointer based on the size of the previously decoded instruction (& remove the hack introduced by commit 34c2f668d0f6b ("MIPS: microMIPS: Add unaligned access support.") which adjusts the instruction pointer in the case of a 16bit sp move instruction, but not any other). Fixes: 34c2f668d0f6b ("MIPS: microMIPS: Add unaligned access support.") Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16953/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-06MIPS: Add DWARF unwinding to assemblyCorey Minyard
This will allow kdump dumps to work correclty with MIPS and future DWARF unwinding of the stack to give accurate tracebacks. Signed-off-by: Corey Minyard <cminyard@mvista.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16990/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-06MIPS: Fix issues in backtracesCorey Minyard
I saw two problems when doing backtraces: The compiler was putting a "fast return" at the top of some functions, before it set up the frame. The backtrace code would stop when it saw a jump instruction, so it would never get to the stack frame setup and would thus misinterpret it. To fix this, don't look for jump instructions until the frame setup has been seen. The assembly code here is: ffffffff80b885a0 <serial8250_handle_irq>: ffffffff80b885a0: c8a00003 bbit0 a1,0x0,ffffffff80b885b0 <serial8250_handle_irq+0x10> ffffffff80b885a4: 0000102d move v0,zero ffffffff80b885a8: 03e00008 jr ra ffffffff80b885ac: 00000000 nop ffffffff80b885b0: 67bdffd0 daddiu sp,sp,-48 ffffffff80b885b4: ffb00008 sd s0,8(sp) The second problem was the compiler was putting the last instruction of the frame save in the delay slot of the jump instruction. If it saved the RA in there, the backtrace could would miss it and misinterpret the frame. To fix this, make sure to process the instruction after the first jump seen. The assembly code for this is: ffffffff80806fd0 <plat_irq_dispatch>: ffffffff80806fd0: 67bdffd0 daddiu sp,sp,-48 ffffffff80806fd4: ffb30020 sd s3,32(sp) ffffffff80806fd8: 24130018 li s3,24 ffffffff80806fdc: ffb20018 sd s2,24(sp) ffffffff80806fe0: 3c12811c lui s2,0x811c ffffffff80806fe4: ffb10010 sd s1,16(sp) ffffffff80806fe8: 3c11811c lui s1,0x811c ffffffff80806fec: ffb00008 sd s0,8(sp) ffffffff80806ff0: 3c10811c lui s0,0x811c ffffffff80806ff4: 08201c03 j ffffffff8080700c <plat_irq_dispa tch+0x3c> ffffffff80806ff8: ffbf0028 sd ra,40(sp) Signed-off-by: Corey Minyard <cminyard@mvista.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16992/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-04fs: fix kernel_read prototypeChristoph Hellwig
Use proper ssize_t and size_t types for the return value and count argument, move the offset last and make it an in/out argument like all other read/write helpers, and make the buf argument a void pointer to get rid of lots of casts in the callers. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-04MIPS: Remove unnecessary inclusions of linux/irqchip/mips-gic.hPaul Burton
linux/irqchip/mips-gic.h is included in a few files that don't actually use it at all. Remove these unnecessary inclusions in preparation for removing the header. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17048/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-04MIPS: Use mips_gic_present() in place of gic_presentPaul Burton
In preparation for removing the gic_present global variable, switch to using the mips_gic_present() function instead. For the most part this is a straightforward substitution. In cases which previously wrapped the GIC case in an #ifdef CONFIG_MIPS_GIC that #ifdef has been removed, since mips_gic_present() will return a compile-time constant false allowing the affected code to be optimised out anyway. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17044/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-04MIPS: VDSO: Drop gic_get_usm_range() usagePaul Burton
We don't really need gic_get_usm_range() to abstract discovery of the address of the GIC user-visible section now that we have access to its base address globally. Switch to calculating it ourselves, which will allow us to stop requiring the irqchip driver to care about a counter exposed to userland for use via the VDSO. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17040/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-04MIPS: CPS: Read GIC_VL_IDENT directly, not via irqchip driverPaul Burton
Rather than calling the gic_read_local_vp_id() function from the GIC irqchip driver, call read_gic_vl_ident() to read the GIC_VL_IDENT register directly. This will allow us to remove gic_read_local_vp_id() from the irqchip driver in a further patch, since that driver doesn't actually care about the register's value. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17023/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-04Merge branch 'linus' into locking/core, to fix up conflictsIngo Molnar
Conflicts: mm/page_alloc.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-30MIPS: CPS: Detect CPUs in secondary clustersPaul Burton
As a first step towards supporting multi-cluster systems, detect cores & VPs in secondary clusters & record their cluster information in the cpu_data array. The "VP topology" line printed during boot is extended to display multiple clusters. On a single cluster it shows output like the following: VP topology: {4,4} This would indicate a system with 2 cores which each contain 4 VPs. We extend this to cover multiple clusters in a natural way: VP topology: {4,4},{2,2} This would indicate a system with 2 clusters. The first cluster contains 2 cores which each contain 4 VPs. The second cluster contains 2 cores which each contain 2 VPs. Actually booting these cores & VPs is left to further patches once other pieces are in place. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17017/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30MIPS: CPS: Cluster support for topology functionsPaul Burton
Modify the functions we use to read information about the topology of the system (the number of cores, VPs & IOCUs that it contains) in order to take into account multiple clusters, and provide a new function to determine the number of clusters in the system. Users of these functions are modified only such that they continue to build successfully - having them actually handle multiple clusters is left to further patches. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17016/ Patchwork: https://patchwork.linux-mips.org/patch/17218/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30MIPS: CPS: Have asm/mips-cps.h include CM & CPC headersPaul Burton
With Coherence Manager (CM) 3.5 information about the topology of the system, which has previously only been available through & accessed from the CM, is now also provided by the Cluster Power Controller (CPC). This includes a new CPC_CONFIG register mirroring GCR_CONFIG, and similarly a new CPC_Cx_CONFIG register mirroring GCR_Cx_CONFIG. In preparation for adjusting functions such as mips_cm_numcores(), which have previously only needed to access the CM, to also access the CPC this patch modifies the way we use the various CPS headers. Rather than having users include asm/mips-cm.h or asm/mips-cpc.h individually we instead have users include asm/mips-cps.h which in turn includes asm/mips-cm.h & asm/mips-cpc.h. This means that users will gain access to both CM & CPC registers by including one header, and most importantly it makes asm/mips-cps.h an ideal location for helper functions which need to access the various components of the CPS. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17015/ Patchwork: https://patchwork.linux-mips.org/patch/17217/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30MIPS: SMP: Allow boot_secondary SMP op to return errorsPaul Burton
Allow the boot_secondary SMP op to return an error to __cpu_up(), which will in turn return it to its caller. This will allow SMP implementations to return errors quickly in cases they they know have failed, rather than relying upon __cpu_up() eventually timing out waiting for the cpu_running completion. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17014/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30MIPS: CM: Add cluster & block args to mips_cm_lock_other()Paul Burton
With CM >= 3.5 we have the notion of multiple clusters & can access their CM, CPC & GIC registers via the apporpriate redirect/other register blocks. In order to allow for this introduce cluster & block arguments to mips_cm_lock_other() which configures the redirect/other region to point at the appropriate cluster, core, VP & register block. Since we now have 4 arguments to mips_cm_lock_other() & a common use is likely to be to target the cluster, core & VP corresponding to a particular Linux CPU number we also add a new mips_cm_lock_other_cpu() helper function which handles that without the caller needing to manually pull out the cluster, core & VP numbers. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17013/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30MIPS: Add CPU cluster number accessorsPaul Burton
Introduce cpu_cluster() & cpu_set_cluster() accessor functions in the same vein as cpu_core(), cpu_vpe_id() & their set variants. These will be used in further patches to allow users to get or set a CPUs cluster number. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17012/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30MIPS: Unify checks for sibling CPUsPaul Burton
Up until now we have open-coded checks for whether CPUs are siblings, with slight variations on whether we consider the package ID or not. This will only get more complex when we introduce cluster support, so in preparation for that this patch introduces a cpus_are_siblings() function which can be used to check whether or not 2 CPUs are siblings in a consistent manner. By checking globalnumber with the VP ID masked out this also has the neat side effect of being ready for multi-cluster systems already. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17011/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30MIPS: Store core & VP IDs in GlobalNumber-style variablePaul Burton
This patch modifies the way we store core & VP IDs such that we store them in a single 32 bit integer whose format matches that of the MIPSr6 GlobalNumber register. Whereas we have previously stored core & VP IDs in separate fields, storing them in a single GlobalNumber-like field: 1) Reduces the size of struct cpuinfo_mips by 4 bytes, and will allow it to not grow when cluster support is added. 2) Gives us a natural place to store cluster number, which matches up with what the architecture provides. 3) Will be useful in the future as a parameter to the MIPSr6 GINVI instruction to specify a target CPU whose icache that instruction should operate on. The cpu_set*() accessor functions are moved out of the asm/cpu-info.h header in order to allow them to use the WARN_ON macro, which is unusable in asm/cpu-info.h due to include ordering. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17010/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30MIPS: Abstract CPU core & VP(E) ID access through accessor functionsPaul Burton
We currently have fields in struct cpuinfo_mips for the core & VP(E) ID of a particular CPU, and various pieces of code directly access those fields. This patch abstracts such access by introducing accessor functions cpu_core(), cpu_set_core(), cpu_vpe_id() & cpu_set_vpe_id() and having code that needs to access these values call those functions rather than directly accessing the struct cpuinfo_mips fields. This prepares us for changes to the way in which those values are stored in later patches. The cpu_vpe_id() function is introduced even though we already had a cpu_vpe_id() macro for a couple of reasons: 1) It's more consistent with the core, and future cluster, accessors. 2) It ensures a sensible return type without explicit casts. 3) It's generally preferable to use functions rather than macros. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17009/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30MIPS: CPS: Use GlobalNumber macros rather than magic numbersPaul Burton
We now have definitions for the GlobalNumber register in asm/mipsregs.h, so use them in place of magic numbers in cps-vec.S. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17008/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30MIPS: CPS: Use change_*, set_* & clear_* where appropriatePaul Burton
Make use of the new change_*, set_* & clear_* accessor functions for CPS (CM, CPC & GIC) registers where doing so makes the code easier to read or shortens it without adversely affecting readability. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17005/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30MIPS: CPC: Use BIT/GENMASK for register fields, order & drop shiftsPaul Burton
Tidy up asm/mips-cpc.h in a similar way to what "MIPS: CM: Use BIT/GENMASK for register fields, order & drop shifts" did for asm/mips-cm.h. We use BIT() & GENMASK() to simplify the definition of register fields, drop the _SHF definitions since that information can be found in the _MSK ones, and then drop the _MSK suffix. Fields definitions are moved to be next to the appropriate register definition, making it easier to link the two & keep everything ordered by register address. Comments are added including the name of each register & a brief description of its purpose which helps to understand what registers are for, link them back to hardware documentation or grep for them. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17003/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: Remove pt_regs adjustments in indirect syscall handlerJames Cowgill
If a restartable syscall is called using the indirect o32 syscall handler - eg: syscall(__NR_waitid, ...), then it is possible for the incorrect arguments to be passed to the syscall after it has been restarted. This is because the syscall handler tries to shift all the registers down one place in pt_regs so that when the syscall is restarted, the "real" syscall is called instead. Unfortunately it only shifts the arguments passed in registers, not the arguments on the user stack. This causes the 4th argument to be duplicated when the syscall is restarted. Fix by removing all the pt_regs shifting so that the indirect syscall handler is called again when the syscall is restarted. The comment "some syscalls like execve get their arguments from struct pt_regs" is long out of date so this should now be safe. Signed-off-by: James Cowgill <James.Cowgill@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Tested-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/15856/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: seccomp: Fix indirect syscall argsJames Hogan
Since commit 669c4092225f ("MIPS: Give __secure_computing() access to syscall arguments."), upon syscall entry when seccomp is enabled, syscall_trace_enter() passes a carefully prepared struct seccomp_data containing syscall arguments to __secure_computing(). Unfortunately it directly uses mips_get_syscall_arg() and fails to take into account the indirect O32 system calls (i.e. syscall(2)) which put the system call number in a0 and have the arguments shifted up by one entry. We can't just revert that commit as samples/bpf/tracex5 would break again, so use syscall_get_arguments() which already takes indirect syscalls into account instead of directly using mips_get_syscall_arg(), similar to what populate_seccomp_data() does. This also removes the redundant error checking of the mips_get_syscall_arg() return value (get_user() already zeroes the result if an argument from the stack can't be loaded). Reported-by: James Cowgill <James.Cowgill@imgtec.com> Fixes: 669c4092225f ("MIPS: Give __secure_computing() access to syscall arguments.") Signed-off-by: James Hogan <james.hogan@imgtec.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: David Daney <david.daney@cavium.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Will Drewry <wad@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16994/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: CM: Use BIT/GENMASK for register fields, order & drop shiftsPaul Burton
There's no reason for us not to use BIT() & GENMASK() in asm/mips-cm.h when declaring macros corresponding to register fields. This patch modifies our definitions to do so. The *_SHF definitions are removed entirely - they duplicate information found in the masks, are infrequently used & can be replaced with use of __ffs() where needed. The *_MSK definitions then lose their _MSK suffix which is now somewhat redundant, and users are modified to match. The field definitions are moved to follow the appropriate register's accessor functions, which helps to keep the field definitions in order & to find the appropriate fields for a given register. Whilst here a comment is added describing each register & including its name, which is helpful both for linking the register back to hardware documentation & for grepping purposes. This also cleans up a couple of issues that became obvious as a result of making the changes described above: - We previously had definitions for GCR_Cx_RESET_EXT_BASE & a phony copy of that named GCR_RESET_EXT_BASE - a register which does not exist. The bad definitions were added by commit 497e803ebf98 ("MIPS: smp-cps: Ensure secondary cores start with EVA disabled") and made use of from boot_core(), which is now modified to use the GCR_Cx_RESET_EXT_BASE definitions. - We had a typo in CM_GCR_ERROR_CAUSE_ERRINGO_MSK - we now correctly define this as inFo rather than inGo. Now that we don't duplicate field information between _SHF & _MSK definitions, and keep the fields next to the register accessors, it will be much easier to spot & prevent any similar oddities being introduced in the future. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Acked-by: Thomas Gleixner <tglx@linutronix.de Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17001/ Patchwork: https://patchwork.linux-mips.org/patch/17216/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: CM: Specify register size when generating accessorsPaul Burton
Some CM registers are always 32 bits, or at least only use bits in the lower 32 bits of the register. For these registers it is wasteful for us to generate accessors which bother to check mips_cm_is64 & perform 64 bit accesses. This patch modifies the accessor generation to take into account the size of the register, and for 32 bit registers we generate accessors which only ever perform 32 bit accesses. For 64 bit registers we either perform a 64 bit access or two 32 bit accesses, depending upon the value of mips_cm_is64. Doing this saves us ~1.5KiB of code in a generic 64r6el kernel, and perhaps more importantly simplifies various code paths. This removes the read64_gcr_* accessors, so mips_cm_error_report() is modified to stop using them & instead use the regular read_gcr_* accessors which will return 64 bit values from the 64 bit registers. The new accessor macros are placed in asm/mips-cps.h such that they can be shared by CPC & GIC code in later patches. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17000/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: CM: Rename mips_cm_base to mips_gcr_basePaul Burton
We currently have a mips_cm_base variable which holds the base address of the Coherence Manager (CM) Global Configuration Registers (GCRs), and accessor functions which use the GCR in their names. This works fine, but gets in the way of sharing the code to generate the accessor functions with other blocks (ie. CPC & GIC) because that code would then need to separately handle the name of the base address variable & the name used in the accessor functions. In order to prepare for sharing the accessor generation code between CM, CPC & GIC code this patch renames mips_cm_base to mips_gcr_base such that the "gcr" portion is common to both the base address variable & the accessor function names. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16999/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: Declare various variables & functions staticPaul Burton
We currently have various variables & functions which are only used within a single translation unit, but which we don't declare static. This causes various sparse warnings of the form: arch/mips/kernel/mips-r2-to-r6-emul.c:49:1: warning: symbol 'mipsr2emustats' was not declared. Should it be static? arch/mips/kernel/unaligned.c:1381:11: warning: symbol 'reg16to32st' was not declared. Should it be static? arch/mips/mm/mmap.c:146:15: warning: symbol 'arch_mmap_rnd' was not declared. Should it be static? Fix these & others by declaring various affected variables & functions static, avoiding the sparse warnings & redundant symbols. [ralf@linux-mips.org: Add Marcin's build fix.] 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/17176/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: Remove plat_timer_setup()Paul Burton
The plat_timer_setup() function is entirely unused - nothing calls it, and no platforms provide it. Perhaps our dummy implementation was once useful as an aid in forward porting platforms, but its time has long since passed so let's remove the dead code. 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/17175/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: Include linux/cpu.h for arch_cpu_idle()Paul Burton
arch/mips/kernel/idle.c provides our implementation of the arch_cpu_idle() function, but doesn't include the linux/cpu.h header which declares it. This leads to a warning from sparse: arch/mips/kernel/idle.c:256:6: warning: symbol 'arch_cpu_idle' was not declared. Should it be static? Fix this by including linux/cpu.h to get the declaration of arch_cpu_idle(). 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/17169/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: signal: Remove unreachable code from force_fcr31_sig().Ralf Baechle
Based on discussion with Linus remove the impossible to reach code rather than replacing it with a BUG(). Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Link: http://lkml.kernel.org/r/20170718140651.15973-4-ebiederm@xmission.com
2017-08-29MIPS: Remove unused ST_OFF from r2300_switch.SPaul Burton
Commit 1a3d59579b9f ("MIPS: Tidy up FPU context switching") removed usage of ST_OFF, leaving it behind as dead code. Commit 828d1e4e9865 ("MIPS: Remove dead define of ST_OFF") then removed the definition of ST_OFF from r4k_switch.S as a cleanup. However the unused definition of ST_OFF has been left behind in r2300_switch.S. Remove it. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16239/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: Move r2300 FP code from r2300_switch.S to r2300_fpu.SPaul Burton
Move _save_fp(), _restore_fp() & _init_fpu() out of r2300_switch.S & into r2300_fpu.S. This logically places all FP-related asm code into r2300_fpu.S & provides consistency with R4K after the preceding commit. Besides cleaning up this will be useful for later patches which disable FP support. [ralf@linux-mips.org: Fixed build issues reported by Arnd Bergmann <arnd@arndb.de>] Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16238/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: Move r4k FP code from r4k_switch.S to r4k_fpu.SPaul Burton
Move _save_fp(), _restore_fp(), _save_msa(), _restore_msa(), _init_msa_upper() & _init_fpu() out of r4k_switch.S & into r4k_fpu.S. This allows us to clean up the way in which Octeon includes the default r4k implementations of these FP functions despite replacing resume(), and makes CONFIG_R4K_FPU more straightforwardly represent all configurations that have an R4K-style FPU, including Octeon. Besides cleaning up this will be useful for later patches which disable FP support. [ralf@linux-mips.org: Fixed build issues reported by Arnd Bergmann <arnd@arndb.de>] Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16237/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: Remove unused R6000 supportPaul Burton
The kernel contains a small amount of incomplete code aimed at supporting old R6000 CPUs. This is: - Unused, as no machine selects CONFIG_SYS_HAS_CPU_R6000. - Broken, since there are glaring errors such as r6000_fpu.S moving the FCSR register to t1, then ignoring it & instead saving t0 into struct sigcontext... - A maintenance headache, since it's code that nobody can test which nevertheless imposes constraints on code which it shares with other machines. Remove this incomplete & broken R6000 CPU support in order to clean up and in preparation for changes which will no longer need to consider dragging the pretense of R6000 support along with them. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16236/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: R6: Constify r2_decoder_tablesMatt Redfearn
The r2_decoder_tables are never modified. They are arrays of constant values and as such should be declared const. This change saves 256 bytes of kernel text, and 128 bytes of kernel data (384 bytes total) on a 32r6el_defconfig (with SMP disabled) Before: text data bss dec hex filename 5576221 1080804 267040 6924065 69a721 vmlinux After: text data bss dec hex filename 5575965 1080676 267040 6923681 69a5a1 vmlinux Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/15289/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29MIPS: SMP: Constify smp opsMatt Redfearn
smp_ops providers do not modify their ops structures, so they should be made const for robustness. Since currently the MIPS kernel is not mapped with memory protection, this does not in itself provide any security benefit, but it still makes sense to make this change. There are also slight code size efficincies from the structure being made read-only, saving 128 bytes of kernel text on a pistachio_defconfig. Before: text data bss dec hex filename 7187239 1772752 470224 9430215 8fe4c7 vmlinux After: text data bss dec hex filename 7187111 1772752 470224 9430087 8fe447 vmlinux Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com> Cc: Bart Van Assche <bart.vanassche@sandisk.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Huacai Chen <chenhc@lemote.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Doug Ledford <dledford@redhat.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Joe Perches <joe@perches.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Steven J. Hill <steven.hill@cavium.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16784/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29smp: Avoid using two cache lines for struct call_single_dataYing Huang
struct call_single_data is used in IPIs to transfer information between CPUs. Its size is bigger than sizeof(unsigned long) and less than cache line size. Currently it is not allocated with any explicit alignment requirements. This makes it possible for allocated call_single_data to cross two cache lines, which results in double the number of the cache lines that need to be transferred among CPUs. This can be fixed by requiring call_single_data to be aligned with the size of call_single_data. Currently the size of call_single_data is the power of 2. If we add new fields to call_single_data, we may need to add padding to make sure the size of new definition is the power of 2 as well. Fortunately, this is enforced by GCC, which will report bad sizes. To set alignment requirements of call_single_data to the size of call_single_data, a struct definition and a typedef is used. To test the effect of the patch, I used the vm-scalability multiple thread swap test case (swap-w-seq-mt). The test will create multiple threads and each thread will eat memory until all RAM and part of swap is used, so that huge number of IPIs are triggered when unmapping memory. In the test, the throughput of memory writing improves ~5% compared with misaligned call_single_data, because of faster IPIs. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Huang, Ying <ying.huang@intel.com> [ Add call_single_data_t and align with size of call_single_data. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Aaron Lu <aaron.lu@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/87bmnqd6lz.fsf@yhuang-mobile.sh.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-17mips/signal: In force_fcr31_sig return in the impossible caseEric W. Biederman
In a recent discussion Maciej Rozycki reported that this case is impossible. Handle the impossible case by just returning instead of trying to handle it. This makes static analysis simpler as it means nothing needs to consider the impossible case after the return statement. As the code no longer has to deal with this case remove FPE_FIXME from the mips siginfo.h Cc: "Maciej W. Rozycki" <macro@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Link: http://lkml.kernel.org/r/20170718140651.15973-4-ebiederm@xmission.com Ref: ea1b75cf9138 ("signal/mips: Document a conflict with SI_USER with SIGFPE") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2017-08-07MIPS: Fix race on setting and getting cpu_online_maskMatija Glavinic Pecotic
While testing cpu hoptlug (cpu down and up in loops) on kernel 4.4, it was observed that occasionally check for cpu online will fail in kernel/cpu.c, _cpu_up: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/tree/kernel/cpu.c?h=v4.4.79#n485 518 /* Arch-specific enabling code. */ 519 ret = __cpu_up(cpu, idle); 520 521 if (ret != 0) 522 goto out_notify; 523 BUG_ON(!cpu_online(cpu)); Reason is race between start_secondary and _cpu_up. cpu_callin_map is set before cpu_online_mask. In __cpu_up, cpu_callin_map is waited for, but cpu online mask is not, resulting in race in which secondary processor started and set cpu_callin_map, but not yet set the online mask,resulting in above BUG being hit. Upstream differs in the area. cpu_online check is in bringup_wait_for_ap, which is after cpu reached AP_ONLINE_IDLE,where secondary passed its start function. Nonetheless, fix makes start_secondary safe and not depending on other locks throughout the code. It protects as well against cpu_online checks put in between sometimes in the future. Fix this by moving completion after all flags are set. Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com> Cc: Alexander Sverdlin <alexander.sverdlin@nokia.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16925/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>