1. 19 May, 2020 1 commit
  2. 17 May, 2020 9 commits
  3. 15 May, 2020 23 commits
  4. 13 May, 2020 1 commit
    • Gustavo A. R. Silva's avatar
      greybus: Replace zero-length array with flexible-array · 84c1e51d
      Gustavo A. R. Silva authored
      The current codebase makes use of the zero-length array language
      extension to the C90 standard, but the preferred mechanism to declare
      variable-length types such as these ones is a flexible array member[1][2],
      introduced in C99:
      
      struct foo {
              int stuff;
              struct boo array[];
      };
      
      By making use of the mechanism above, we will get a compiler warning
      in case the flexible array does not occur last in the structure, which
      will help us prevent some kind of undefined behavior bugs from being
      inadvertently introduced[3] to the codebase from now on.
      
      Also, notice that, dynamic memory allocations won't be affected by
      this change:
      
      "Flexible array members have incomplete type, and so the sizeof operator
      may not be applied. As a quirk of the original implementation of
      zero-length arrays, sizeof evaluates to zero."[1]
      
      sizeof(flexible-array-member) triggers a warning because flexible array
      members have incomplete type[1]. There are some instances of code in
      which the sizeof operator is being incorrectly/erroneously applied to
      zero-length arrays and the result is zero. Such instances may be hiding
      some bugs. So, this work (flexible-array member conversions) will also
      help to get completely rid of those sorts of issues.
      
      This issue was found with the help of Coccinelle.
      
      [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
      [2] https://github.com/KSPP/linux/issues/21
      [3] commit 76497732 ("cxgb3/l2t: Fix undefined behaviour")
      Signed-off-by: default avatarGustavo A. R. Silva <gustavoars@kernel.org>
      Link: https://lore.kernel.org/r/20200507185318.GA14393@embeddedorSigned-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      84c1e51d
  5. 11 May, 2020 1 commit
  6. 10 May, 2020 5 commits
    • Linus Torvalds's avatar
      Linux 5.7-rc5 · 2ef96a5b
      Linus Torvalds authored
      2ef96a5b
    • Linus Torvalds's avatar
      Merge tag 'x86-urgent-2020-05-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · c14cab26
      Linus Torvalds authored
      Pull x86 fixes from Thomas Gleixner:
       "A set of fixes for x86:
      
         - Ensure that direct mapping alias is always flushed when changing
           page attributes. The optimization for small ranges failed to do so
           when the virtual address was in the vmalloc or module space.
      
         - Unbreak the trace event registration for syscalls without arguments
           caused by the refactoring of the SYSCALL_DEFINE0() macro.
      
         - Move the printk in the TSC deadline timer code to a place where it
           is guaranteed to only be called once during boot and cannot be
           rearmed by clearing warn_once after boot. If it's invoked post boot
           then lockdep rightfully complains about a potential deadlock as the
           calling context is different.
      
         - A series of fixes for objtool and the ORC unwinder addressing
           variety of small issues:
      
             - Stack offset tracking for indirect CFAs in objtool ignored
               subsequent pushs and pops
      
             - Repair the unwind hints in the register clearing entry ASM code
      
             - Make the unwinding in the low level exit to usermode code stop
               after switching to the trampoline stack. The unwind hint is no
               longer valid and the ORC unwinder emits a warning as it can't
               find the registers anymore.
      
             - Fix unwind hints in switch_to_asm() and rewind_stack_do_exit()
               which caused objtool to generate bogus ORC data.
      
             - Prevent unwinder warnings when dumping the stack of a
               non-current task as there is no way to be sure about the
               validity because the dumped stack can be a moving target.
      
             - Make the ORC unwinder behave the same way as the frame pointer
               unwinder when dumping an inactive tasks stack and do not skip
               the first frame.
      
             - Prevent ORC unwinding before ORC data has been initialized
      
             - Immediately terminate unwinding when a unknown ORC entry type
               is found.
      
             - Prevent premature stop of the unwinder caused by IRET frames.
      
             - Fix another infinite loop in objtool caused by a negative
               offset which was not catched.
      
             - Address a few build warnings in the ORC unwinder and add
               missing static/ro_after_init annotations"
      
      * tag 'x86-urgent-2020-05-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        x86/unwind/orc: Move ORC sorting variables under !CONFIG_MODULES
        x86/apic: Move TSC deadline timer debug printk
        ftrace/x86: Fix trace event registration for syscalls without arguments
        x86/mm/cpa: Flush direct map alias during cpa
        objtool: Fix infinite loop in for_offset_range()
        x86/unwind/orc: Fix premature unwind stoppage due to IRET frames
        x86/unwind/orc: Fix error path for bad ORC entry type
        x86/unwind/orc: Prevent unwinding before ORC initialization
        x86/unwind/orc: Don't skip the first frame for inactive tasks
        x86/unwind: Prevent false warnings for non-current tasks
        x86/unwind/orc: Convert global variables to static
        x86/entry/64: Fix unwind hints in rewind_stack_do_exit()
        x86/entry/64: Fix unwind hints in __switch_to_asm()
        x86/entry/64: Fix unwind hints in kernel exit path
        x86/entry/64: Fix unwind hints in register clearing code
        objtool: Fix stack offset tracking for indirect CFAs
      c14cab26
    • Linus Torvalds's avatar
      Merge tag 'objtool-urgent-2020-05-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 8b000832
      Linus Torvalds authored
      Pull objtool fix from Thomas Gleixner:
       "A single fix for objtool to prevent an infinite loop in the
        jump table search which can be triggered when building the
        kernel with '-ffunction-sections'"
      
      * tag 'objtool-urgent-2020-05-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        objtool: Fix infinite loop in find_jump_table()
      8b000832
    • Linus Torvalds's avatar
      Merge tag 'locking-urgent-2020-05-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · bd2049f8
      Linus Torvalds authored
      Pull locking fix from Thomas Gleixner:
       "A single fix for the fallout of the recent futex uacess rework.
      
        With those changes GCC9 fails to analyze arch_futex_atomic_op_inuser()
        correctly and emits a 'maybe unitialized' warning. While we usually
        ignore compiler stupidity the conditional store is pointless anyway
        because the correct case has to store. For the fault case the extra
        store does no harm"
      
      * tag 'locking-urgent-2020-05-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        ARM: futex: Address build warning
      bd2049f8
    • Linus Torvalds's avatar
      Merge tag 'iommu-fixes-v5.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu · 27d2dcb1
      Linus Torvalds authored
      Pull iommu fixes from Joerg Roedel:
      
       - Race condition fixes for the AMD IOMMU driver.
      
         These are five patches fixing two race conditions around
         increase_address_space(). The first race condition was around the
         non-atomic update of the domain page-table root pointer and the
         variable containing the page-table depth (called mode). This is fixed
         now be merging page-table root and mode into one 64-bit field which
         is read/written atomically.
      
         The second race condition was around updating the page-table root
         pointer and making it public before the hardware caches were flushed.
         This could cause addresses to be mapped and returned to drivers which
         are not reachable by IOMMU hardware yet, causing IO page-faults. This
         is fixed too by adding the necessary flushes before a new page-table
         root is published.
      
         Related to the race condition fixes these patches also add a missing
         domain_flush_complete() barrier to update_domain() and a fix to bail
         out of the loop which tries to increase the address space when the
         call to increase_address_space() fails.
      
         Qian was able to trigger the race conditions under high load and
         memory pressure within a few days of testing. He confirmed that he
         has seen no issues anymore with the fixes included here.
      
       - Fix for a list-handling bug in the VirtIO IOMMU driver.
      
      * tag 'iommu-fixes-v5.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
        iommu/virtio: Reverse arguments to list_add
        iommu/amd: Do not flush Device Table in iommu_map_page()
        iommu/amd: Update Device Table in increase_address_space()
        iommu/amd: Call domain_flush_complete() in update_domain()
        iommu/amd: Do not loop forever when trying to increase address space
        iommu/amd: Fix race in increase_address_space()/fetch_pte()
      27d2dcb1