kernel.git/arch/powerpc/kernel/head_64.S, branch linux-6.1.y

Merge tag 'bitmap-6.1-rc1' of https://github.com/norov/linux

2022-10-10T19:49:34Z

Pull bitmap updates from Yury Norov: - Fix unsigned comparison to -1 in CPUMAP_FILE_MAX_BYTES (Phil Auld) - cleanup nr_cpu_ids vs nr_cpumask_bits mess (me) This series cleans that mess and adds new config FORCE_NR_CPUS that allows to optimize cpumask subsystem if the number of CPUs is known at compile-time. - optimize find_bit() functions (me) Reworks find_bit() functions based on new FIND_{FIRST,NEXT}_BIT() macros. - add find_nth_bit() (me) Adds find_nth_bit(), which is ~70 times faster than bitcounting with for_each() loop: for_each_set_bit(bit, mask, size) if (n-- == 0) return bit; Also adds bitmap_weight_and() to let people replace this pattern: tmp = bitmap_alloc(nbits); bitmap_and(tmp, map1, map2, nbits); weight = bitmap_weight(tmp, nbits); bitmap_free(tmp); with a single bitmap_weight_and() call. - repair cpumask_check() (me) After switching cpumask to use nr_cpu_ids, cpumask_check() started generating many false-positive warnings. This series fixes it. - Add for_each_cpu_andnot() and for_each_cpu_andnot() (Valentin Schneider) Extends the API with one more function and applies it in sched/core. * tag 'bitmap-6.1-rc1' of https://github.com/norov/linux: (28 commits) sched/core: Merge cpumask_andnot()+for_each_cpu() into for_each_cpu_andnot() lib/test_cpumask: Add for_each_cpu_and(not) tests cpumask: Introduce for_each_cpu_andnot() lib/find_bit: Introduce find_next_andnot_bit() cpumask: fix checking valid cpu range lib/bitmap: add tests for for_each() loops lib/find: optimize for_each() macros lib/bitmap: introduce for_each_set_bit_wrap() macro lib/find_bit: add find_next{,_and}_bit_wrap cpumask: switch for_each_cpu{,_not} to use for_each_bit() net: fix cpu_max_bits_warn() usage in netif_attrmask_next{,_and} cpumask: add cpumask_nth_{,and,andnot} lib/bitmap: remove bitmap_ord_to_pos lib/bitmap: add tests for find_nth_bit() lib: add find_nth{,_and,_andnot}_bit() lib/bitmap: add bitmap_weight_and() lib/bitmap: don't call __bitmap_weight() in kernel code tools: sync find_bit() implementation lib/find_bit: optimize find_next_bit() functions lib/find_bit: create find_first_zero_bit_le() ...

powerpc/64s/interrupt: halt early boot interrupts if paca is not set up

2022-09-28T09:22:13Z

Ensure r13 is zero from very early in boot until it gets set to the boot paca pointer. This allows early program and mce handlers to halt if there is no valid paca, rather than potentially run off into the weeds. This preserves register and memory contents for low level debugging tools. Nothing could be printed to console at this point in any case because even udbg is only set up after the boot paca is set, so this shouldn't be missed. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220926055620.2676869-6-npiggin@gmail.com

powerpc/64: provide a helper macro to load r2 with the kernel TOC

2022-09-28T09:22:12Z

A later change stops the kernel using r2 and loads it with a poison value. Provide a PACATOC loading abstraction which can hide this detail. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220926034057.2360083-5-npiggin@gmail.com

powerpc/64: use 32-bit immediate for STACK_FRAME_REGS_MARKER

2022-09-28T09:22:12Z

Using a 32-bit constant for this marker allows it to be loaded with two ALU instructions, like 32-bit. This avoids a TOC entry and a TOC load that depends on the r2 value that has just been loaded from the PACA. This changes the value for 32-bit as well, so both have the same value in the low 4 bytes and 64-bit has 0 in the top bytes. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220926034057.2360083-2-npiggin@gmail.com

powerpc: Remove CONFIG_PPC_BOOK3E

2022-09-26T13:00:13Z

CONFIG_PPC_BOOK3E is redundant with CONFIG_PPC_BOOK3E_64. The later is more explicit about the fact that it's a 64 bits target. Remove CONFIG_PPC_BOOK3E. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/5d0891490813c19cdcfc04678f512ea68cba3e64.1663606876.git.christophe.leroy@csgroup.eu

powerpc/64: don't refer nr_cpu_ids in asm code when it's undefined

2022-09-20T23:11:44Z

generic_secondary_common_init() calls LOAD_REG_ADDR(r7, nr_cpu_ids) conditionally on CONFIG_SMP. However, if 'NR_CPUS == 1', kernel doesn't use the nr_cpu_ids, and in C code, it's just: #if NR_CPUS == 1 #define nr_cpu_ids ... This series makes declaration of nr_cpu_ids conditional on NR_CPUS == 1, and that reveals the issue, because compiler can't link the LOAD_REG_ADDR(r7, nr_cpu_ids) against nonexisting symbol. Current code looks unsafe for those who build kernel with CONFIG_SMP=y and NR_CPUS == 1. This is weird configuration, but not disallowed. Fix the linker error by replacing LOAD_REG_ADDR() with LOAD_REG_IMMEDIATE() conditionally on NR_CPUS == 1. As the following patch adds CONFIG_FORCE_NR_CPUS option that has the similar effect on nr_cpu_ids, make the generic_secondary_common_init() conditional on it too. Reported-by: Stephen Rothwell Signed-off-by: Yury Norov

powerpc/64e: KASAN Full support for BOOK3E/64

2022-06-29T07:04:15Z

We now have memory organised in a way that allows implementing KASAN. Unlike book3s/64, book3e always has translation active so the only thing needed to use KASAN is to setup an early zero shadow mapping just after setting a stack pointer and before calling early_setup(). The memory layout is now as follows +------------------------+ Kernel virtual map end (0xc000200000000000) | | | 16TB of KASAN map | | | +------------------------+ Kernel KASAN shadow map start | | | 16TB of IO map | | | +------------------------+ Kernel IO map start | | | 16TB of vmemmap | | | +------------------------+ Kernel vmemmap start | | | 16TB of vmap | | | +------------------------+ Kernel virt start (0xc000100000000000) | | | 64TB of linear mem | | | +------------------------+ Kernel linear (0xc.....) Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/0bef8beda27baf71e3b9e8b13e620fba6e19499b.1656427701.git.christophe.leroy@csgroup.eu

powerpc: Fix all occurences of "the the"

2022-05-22T05:59:43Z

Rather than waiting for the bots to fix these one-by-one, fix all occurences of "the the" throughout arch/powerpc. Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220518142629.513007-1-mpe@ellerman.id.au

powerpc: Replace PPC64_ELF_ABI_v{1/2} by CONFIG_PPC64_ELF_ABI_V{1/2}

2022-05-19T13:11:29Z

Replace all uses of PPC64_ELF_ABI_v1 and PPC64_ELF_ABI_v2 by resp CONFIG_PPC64_ELF_ABI_V1 and CONFIG_PPC64_ELF_ABI_V2. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/ba13d59e8c50bc9aa6328f1c7f0c0d0278e0a3a7.1652074503.git.christophe.leroy@csgroup.eu

powerpc/64/asm: Do not reassign labels

2021-12-23T11:35:12Z

The LLVM integrated assembler really does not like us reassigning things to the same label: :7:9: error: invalid reassignment of non-absolute variable 'fs_label' This happens across a bunch of platforms: https://github.com/ClangBuiltLinux/linux/issues/1043 https://github.com/ClangBuiltLinux/linux/issues/1008 https://github.com/ClangBuiltLinux/linux/issues/920 https://github.com/ClangBuiltLinux/linux/issues/1050 There is no hope of getting this fixed in LLVM (see https://github.com/ClangBuiltLinux/linux/issues/1043#issuecomment-641571200 and https://bugs.llvm.org/show_bug.cgi?id=47798#c1 ) so if we want to build with LLVM_IAS, we need to hack around it ourselves. For us the big problem comes from this: \#define USE_FIXED_SECTION(sname) \ fs_label = start_##sname; \ fs_start = sname##_start; \ use_ftsec sname; \#define USE_TEXT_SECTION() fs_label = start_text; \ fs_start = text_start; \ .text and in particular fs_label. This works around it by not setting those 'variables' and requiring that users of the variables instead track for themselves what section they are in. This isn't amazing, by any stretch, but it gets us further in the compilation. Note that even though users have to keep track of the section, using a wrong one produces an error with both binutils and llvm which prevents from using wrong section at the compile time: llvm error example: AS arch/powerpc/kernel/head_64.o :0: error: Cannot represent a difference across sections make[3]: *** [/home/aik/p/kernels-llvm/llvm/scripts/Makefile.build:388: arch/powerpc/kernel/head_64.o] Error 1 binutils error example: /home/aik/p/kernels-llvm/llvm/arch/powerpc/kernel/exceptions-64s.S: Assembler messages: /home/aik/p/kernels-llvm/llvm/arch/powerpc/kernel/exceptions-64s.S:1974: Error: can't resolve `system_call_common' {.text section} - `start_r eal_vectors' {.head.text.real_vectors section} make[3]: *** [/home/aik/p/kernels-llvm/llvm/scripts/Makefile.build:388: arch/powerpc/kernel/head_64.o] Error 1 Signed-off-by: Daniel Axtens Signed-off-by: Alexey Kardashevskiy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211221055904.555763-5-aik@ozlabs.ru