diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-07-31 09:33:45 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-07-31 09:33:45 -0700 |
| commit | c1954ca6abdc69a02a768368eb31882e92cf5bfa (patch) | |
| tree | 1138c65f49c19b8e45352645a43cdada944bfbd6 | |
| parent | ae2911de2eb5dc9ccb88c6502c776a8fbb7acc67 (diff) | |
| parent | 5c6360ee4a0e7f62de34341ad5d3c936f49b391d (diff) | |
Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM fixes from Russell King:
- avoid invoking overflow handler for uaccess watchpoints
- fix incorrect clock_gettime64 availability
- fix EFI crash in create_mapping_late()
* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: 8988/1: mmu: fix crash in EFI calls due to p4d typo in create_mapping_late()
ARM: 8987/1: VDSO: Fix incorrect clock_gettime64
ARM: 8986/1: hw_breakpoint: Don't invoke overflow handler on uaccess watchpoints
| -rw-r--r-- | arch/arm/kernel/hw_breakpoint.c | 27 | ||||
| -rw-r--r-- | arch/arm/kernel/vdso.c | 1 | ||||
| -rw-r--r-- | arch/arm/mm/mmu.c | 2 |
3 files changed, 24 insertions, 6 deletions
diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c index 02ca7adf5375..7fff88e61252 100644 --- a/arch/arm/kernel/hw_breakpoint.c +++ b/arch/arm/kernel/hw_breakpoint.c @@ -683,6 +683,12 @@ static void disable_single_step(struct perf_event *bp) arch_install_hw_breakpoint(bp); } +static int watchpoint_fault_on_uaccess(struct pt_regs *regs, + struct arch_hw_breakpoint *info) +{ + return !user_mode(regs) && info->ctrl.privilege == ARM_BREAKPOINT_USER; +} + static void watchpoint_handler(unsigned long addr, unsigned int fsr, struct pt_regs *regs) { @@ -742,16 +748,27 @@ static void watchpoint_handler(unsigned long addr, unsigned int fsr, } pr_debug("watchpoint fired: address = 0x%x\n", info->trigger); + + /* + * If we triggered a user watchpoint from a uaccess routine, + * then handle the stepping ourselves since userspace really + * can't help us with this. + */ + if (watchpoint_fault_on_uaccess(regs, info)) + goto step; + perf_bp_event(wp, regs); /* - * If no overflow handler is present, insert a temporary - * mismatch breakpoint so we can single-step over the - * watchpoint trigger. + * Defer stepping to the overflow handler if one is installed. + * Otherwise, insert a temporary mismatch breakpoint so that + * we can single-step over the watchpoint trigger. */ - if (is_default_overflow_handler(wp)) - enable_single_step(wp, instruction_pointer(regs)); + if (!is_default_overflow_handler(wp)) + goto unlock; +step: + enable_single_step(wp, instruction_pointer(regs)); unlock: rcu_read_unlock(); } diff --git a/arch/arm/kernel/vdso.c b/arch/arm/kernel/vdso.c index 6bfdca4769a7..fddd08a6e063 100644 --- a/arch/arm/kernel/vdso.c +++ b/arch/arm/kernel/vdso.c @@ -184,6 +184,7 @@ static void __init patch_vdso(void *ehdr) if (!cntvct_ok) { vdso_nullpatch_one(&einfo, "__vdso_gettimeofday"); vdso_nullpatch_one(&einfo, "__vdso_clock_gettime"); + vdso_nullpatch_one(&einfo, "__vdso_clock_gettime64"); } } diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index 628028bfbb92..bcd82614c25d 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -966,7 +966,7 @@ void __init create_mapping_late(struct mm_struct *mm, struct map_desc *md, pud_t *pud; p4d = p4d_alloc(mm, pgd_offset(mm, md->virtual), md->virtual); - if (!WARN_ON(!p4d)) + if (WARN_ON(!p4d)) return; pud = pud_alloc(mm, p4d, md->virtual); if (WARN_ON(!pud)) |