Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Catalin Marinas:

 - Update the linker script to use L1_CACHE_BYTES instead of hard-coded
   64.  We recently changed L1_CACHE_BYTES to 128

 - Improve race condition reporting on set_pte_at() and change the BUG
   to WARN_ONCE.  With hardware update of the accessed/dirty state, we
   need to ensure that set_pte_at() does not inadvertently override
   hardware updated state.  The patch also makes the checks ignore
   !pte_valid() new entries

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: Improve error reporting on set_pte_at() checks
  arm64: update linker script to increased L1_CACHE_BYTES value

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 7e074f9..63f52b5 100644 (file)
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -276,10 +276,14 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
         * hardware updates of the pte (ptep_set_access_flags safely changes
         * valid ptes without going through an invalid entry).
         */
-       if (IS_ENABLED(CONFIG_DEBUG_VM) && IS_ENABLED(CONFIG_ARM64_HW_AFDBM) &&
-           pte_valid(*ptep)) {
-               BUG_ON(!pte_young(pte));
-               BUG_ON(pte_write(*ptep) && !pte_dirty(pte));
+       if (IS_ENABLED(CONFIG_ARM64_HW_AFDBM) &&
+           pte_valid(*ptep) && pte_valid(pte)) {
+               VM_WARN_ONCE(!pte_young(pte),
+                            "%s: racy access flag clearing: 0x%016llx -> 0x%016llx",
+                            __func__, pte_val(*ptep), pte_val(pte));
+               VM_WARN_ONCE(pte_write(*ptep) && !pte_dirty(pte),
+                            "%s: racy dirty state clearing: 0x%016llx -> 0x%016llx",
+                            __func__, pte_val(*ptep), pte_val(pte));
        }
 
        set_pte(ptep, pte);

diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index 1ee2c39..71426a7 100644 (file)
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -5,6 +5,7 @@
  */
 
 #include <asm-generic/vmlinux.lds.h>
+#include <asm/cache.h>
 #include <asm/kernel-pgtable.h>
 #include <asm/thread_info.h>
 #include <asm/memory.h>
@@ -140,7 +141,7 @@ SECTIONS
                ARM_EXIT_KEEP(EXIT_DATA)
        }
 
-       PERCPU_SECTION(64)
+       PERCPU_SECTION(L1_CACHE_BYTES)
 
        . = ALIGN(PAGE_SIZE);
        __init_end = .;
@@ -158,7 +159,7 @@ SECTIONS
        . = ALIGN(PAGE_SIZE);
        _data = .;
        _sdata = .;
-       RW_DATA_SECTION(64, PAGE_SIZE, THREAD_SIZE)
+       RW_DATA_SECTION(L1_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE)
        PECOFF_EDATA_PADDING
        _edata = .;