From 606f95e4255845155f62504a9e1f12665b1853c8 Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Thu, 21 Sep 2017 21:52:08 +0200 Subject: [PATCH] parisc: Add HWPOISON page fault handler code Commit 24587380f61d ("parisc: Add MADV_HWPOISON and MADV_SOFT_OFFLINE") added the necessary constants to handle hardware-poisoning. Those were needed to support the page deallocation feature from firmware. But I completely missed to add the relevant fault handler code. This now showed up when I ran the madvise07 testcase from the Linux Test Project, which failed with a kernel BUG at arch/parisc/mm/fault.c:320. With this patch the parisc kernel now behaves like other platforms and gives the same kernel syslog warnings when poisoning pages. Signed-off-by: Helge Deller --- arch/parisc/mm/fault.c | 33 +++++++++++++++++++++++++++++---- 1 file changed, 29 insertions(+), 4 deletions(-) diff --git a/arch/parisc/mm/fault.c b/arch/parisc/mm/fault.c index 5b101f6a5607..e247edbca68e 100644 --- a/arch/parisc/mm/fault.c +++ b/arch/parisc/mm/fault.c @@ -17,6 +17,7 @@ #include #include #include +#include #include @@ -261,7 +262,7 @@ void do_page_fault(struct pt_regs *regs, unsigned long code, struct task_struct *tsk; struct mm_struct *mm; unsigned long acc_type; - int fault; + int fault = 0; unsigned int flags; if (faulthandler_disabled()) @@ -315,7 +316,8 @@ good_area: goto out_of_memory; else if (fault & VM_FAULT_SIGSEGV) goto bad_area; - else if (fault & VM_FAULT_SIGBUS) + else if (fault & (VM_FAULT_SIGBUS|VM_FAULT_HWPOISON| + VM_FAULT_HWPOISON_LARGE)) goto bad_area; BUG(); } @@ -352,8 +354,7 @@ bad_area: if (user_mode(regs)) { struct siginfo si; - - show_signal_msg(regs, code, address, tsk, vma); + unsigned int lsb = 0; switch (code) { case 15: /* Data TLB miss fault/Data page fault */ @@ -386,6 +387,30 @@ bad_area: si.si_code = (code == 26) ? SEGV_ACCERR : SEGV_MAPERR; break; } + +#ifdef CONFIG_MEMORY_FAILURE + if (fault & (VM_FAULT_HWPOISON|VM_FAULT_HWPOISON_LARGE)) { + printk(KERN_ERR + "MCE: Killing %s:%d due to hardware memory corruption fault at %08lx\n", + tsk->comm, tsk->pid, address); + si.si_signo = SIGBUS; + si.si_code = BUS_MCEERR_AR; + } +#endif + + /* + * Either small page or large page may be poisoned. + * In other words, VM_FAULT_HWPOISON_LARGE and + * VM_FAULT_HWPOISON are mutually exclusive. + */ + if (fault & VM_FAULT_HWPOISON_LARGE) + lsb = hstate_index_to_shift(VM_FAULT_GET_HINDEX(fault)); + else if (fault & VM_FAULT_HWPOISON) + lsb = PAGE_SHIFT; + else + show_signal_msg(regs, code, address, tsk, vma); + si.si_addr_lsb = lsb; + si.si_errno = 0; si.si_addr = (void __user *) address; force_sig_info(si.si_signo, &si, current);