linux-toradex.git/arch/riscv/include, branch v5.9

RISC-V: Check clint_time_val before use

2020-09-30T18:05:14+00:00

The NoMMU kernel is broken for QEMU virt machine from Linux-5.9-rc6
because clint_time_val is used even before CLINT driver is probed
at following places:
1. rand_initialize() calls get_cycles() which in-turn uses
   clint_time_val
2. boot_init_stack_canary() calls get_cycles() which in-turn
   uses clint_time_val

The issue#1 (above) is fixed by providing custom random_get_entropy()
for RISC-V NoMMU kernel. For issue#2 (above), we remove dependency of
boot_init_stack_canary() on get_cycles() and this is aligned with the
boot_init_stack_canary() implementations of ARM, ARM64 and MIPS kernel.

Fixes: d5be89a8d118 ("RISC-V: Resurrect the MMIO timer implementation for M-mode systems")
Signed-off-by: Anup Patel 
Tested-by: Damien Le Moal 
Signed-off-by: Palmer Dabbelt

RISC-V: Resurrect the MMIO timer implementation for M-mode systems

2020-09-19T20:21:11+00:00

The K210 doesn't implement rdtime in M-mode, and since that's where Linux runs
in the NOMMU systems that means we can't use rdtime.  The K210 is the only
system that anyone is currently running NOMMU or M-mode on, so here we're just
inlining the timer read directly.

This also adds the CLINT driver as an !MMU dependency, as it's currently the
only timer driver availiable for these systems and without it we get a build
failure for some configurations.

Tested-by: Damien Le Moal 
Signed-off-by: Palmer Dabbelt

RISC-V: Take text_mutex in ftrace_init_nop()

2020-09-11T19:15:21+00:00

Without this we get lockdep failures.  They're spurious failures as SMP isn't
up when ftrace_init_nop() is called.  As far as I can tell the easiest fix is
to just take the lock, which also seems like the safest fix.

Signed-off-by: Palmer Dabbelt 
Acked-by: Guo Ren 
Signed-off-by: Palmer Dabbelt

RISC-V: Remove CLINT related code from timer and arch

2020-08-20T17:58:13+00:00

Right now the RISC-V timer driver is convoluted to support:
1. Linux RISC-V S-mode (with MMU) where it will use TIME CSR for
   clocksource and SBI timer calls for clockevent device.
2. Linux RISC-V M-mode (without MMU) where it will use CLINT MMIO
   counter register for clocksource and CLINT MMIO compare register
   for clockevent device.

We now have a separate CLINT timer driver which also provide CLINT
based IPI operations so let's remove CLINT MMIO related code from
arch/riscv directory and RISC-V timer driver.

Signed-off-by: Anup Patel 
Tested-by: Emil Renner Berhing 
Acked-by: Daniel Lezcano 
Reviewed-by: Atish Patra 
Reviewed-by: Palmer Dabbelt 
Signed-off-by: Palmer Dabbelt

RISC-V: Add mechanism to provide custom IPI operations

2020-08-20T17:55:40+00:00

We add mechanism to set custom IPI operations so that CLINT driver
from drivers directory can provide custom IPI operations.

Signed-off-by: Anup Patel 
Tested-by: Emil Renner Berhing 
Reviewed-by: Atish Patra 
Reviewed-by: Palmer Dabbelt 
Signed-off-by: Palmer Dabbelt

Merge tag 'timers-urgent-2020-08-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2020-08-14T21:26:08+00:00

Pull timekeeping updates from Thomas Gleixner:
 "A set of timekeeping/VDSO updates:

   - Preparatory work to allow S390 to switch over to the generic VDSO
     implementation.

     S390 requires that the VDSO data pointer is handed in to the
     counter read function when time namespace support is enabled.
     Adding the pointer is a NOOP for all other architectures because
     the compiler is supposed to optimize that out when it is unused in
     the architecture specific inline. The change also solved a similar
     problem for MIPS which fortunately has time namespaces not yet
     enabled.

     S390 needs to update clock related VDSO data independent of the
     timekeeping updates. This was solved so far with yet another
     sequence counter in the S390 implementation. A better solution is
     to utilize the already existing VDSO sequence count for this. The
     core code now exposes helper functions which allow to serialize
     against the timekeeper code and against concurrent readers.

     S390 needs extra data for their clock readout function. The initial
     common VDSO data structure did not provide a way to add that. It
     now has an embedded architecture specific struct embedded which
     defaults to an empty struct.

     Doing this now avoids tree dependencies and conflicts post rc1 and
     allows all other architectures which work on generic VDSO support
     to work from a common upstream base.

   - A trivial comment fix"

* tag 'timers-urgent-2020-08-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  time: Delete repeated words in comments
  lib/vdso: Allow to add architecture-specific vdso data
  timekeeping/vsyscall: Provide vdso_update_begin/end()
  vdso/treewide: Add vdso_data pointer argument to __arch_get_hw_counter()

uaccess: remove segment_eq

2020-08-12T17:57:58+00:00

segment_eq is only used to implement uaccess_kernel.  Just open code
uaccess_kernel in the arch uaccess headers and remove one layer of
indirection.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Andrew Morton 
Acked-by: Linus Torvalds 
Acked-by: Greentime Hu 
Acked-by: Geert Uytterhoeven 
Cc: Nick Hu 
Cc: Vincent Chen 
Cc: Paul Walmsley 
Cc: Palmer Dabbelt 
Link: http://lkml.kernel.org/r/20200710135706.537715-5-hch@lst.de
Signed-off-by: Linus Torvalds

riscv: include in

2020-08-12T17:57:58+00:00

To ensure TASK_SIZE is defined for USER_DS.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Andrew Morton 
Acked-by: Linus Torvalds 
Acked-by: Palmer Dabbelt 
Cc: Nick Hu 
Cc: Greentime Hu 
Cc: Vincent Chen 
Cc: Paul Walmsley 
Cc: Geert Uytterhoeven 
Link: http://lkml.kernel.org/r/20200710135706.537715-4-hch@lst.de
Signed-off-by: Linus Torvalds

Merge branch 'akpm' (patches from Andrew)

2020-08-07T18:39:33+00:00

Merge misc updates from Andrew Morton:

 - a few MM hotfixes

 - kthread, tools, scripts, ntfs and ocfs2

 - some of MM

Subsystems affected by this patch series: kthread, tools, scripts, ntfs,
ocfs2 and mm (hofixes, pagealloc, slab-generic, slab, slub, kcsan,
debug, pagecache, gup, swap, shmem, memcg, pagemap, mremap, mincore,
sparsemem, vmalloc, kasan, pagealloc, hugetlb and vmscan).

* emailed patches from Andrew Morton : (162 commits)
  mm: vmscan: consistent update to pgrefill
  mm/vmscan.c: fix typo
  khugepaged: khugepaged_test_exit() check mmget_still_valid()
  khugepaged: retract_page_tables() remember to test exit
  khugepaged: collapse_pte_mapped_thp() protect the pmd lock
  khugepaged: collapse_pte_mapped_thp() flush the right range
  mm/hugetlb: fix calculation of adjust_range_if_pmd_sharing_possible
  mm: thp: replace HTTP links with HTTPS ones
  mm/page_alloc: fix memalloc_nocma_{save/restore} APIs
  mm/page_alloc.c: skip setting nodemask when we are in interrupt
  mm/page_alloc: fallbacks at most has 3 elements
  mm/page_alloc: silence a KASAN false positive
  mm/page_alloc.c: remove unnecessary end_bitidx for [set|get]_pfnblock_flags_mask()
  mm/page_alloc.c: simplify pageblock bitmap access
  mm/page_alloc.c: extract the common part in pfn_to_bitidx()
  mm/page_alloc.c: replace the definition of NR_MIGRATETYPE_BITS with PB_migratetype_bits
  mm/shuffle: remove dynamic reconfiguration
  mm/memory_hotplug: document why shuffle_zone() is relevant
  mm/page_alloc: remove nr_free_pagecache_pages()
  mm: remove vm_total_pages
  ...

asm-generic: pgalloc: provide generic pgd_free()

2020-08-07T18:33:26+00:00

Most architectures define pgd_free() as a wrapper for free_page().

Provide a generic version in asm-generic/pgalloc.h and enable its use for
most architectures.

Signed-off-by: Mike Rapoport 
Signed-off-by: Andrew Morton 
Reviewed-by: Pekka Enberg 
Acked-by: Geert Uytterhoeven 	[m68k]
Cc: Abdul Haleem 
Cc: Andy Lutomirski 
Cc: Arnd Bergmann 
Cc: Christophe Leroy 
Cc: Joerg Roedel 
Cc: Joerg Roedel 
Cc: Max Filippov 
Cc: Peter Zijlstra (Intel) 
Cc: Satheesh Rajendran 
Cc: Stafford Horne 
Cc: Stephen Rothwell 
Cc: Steven Rostedt 
Cc: Matthew Wilcox 
Link: http://lkml.kernel.org/r/20200627143453.31835-7-rppt@kernel.org
Signed-off-by: Linus Torvalds