From: "Jonathan (Zhixiong) Zhang" <[email protected]> Add VM_FAULT_HWPOISON[_LARGE] handling to the arm64 page fault handler. Handling of VM_FAULT_HWPOISON[_LARGE] is very similar to VM_FAULT_OOM, the only difference is that a different si_code (BUS_MCEERR_AR) is passed to user space and si_addr_lsb field is initialized.
Signed-off-by: Jonathan (Zhixiong) Zhang <[email protected]> Signed-off-by: Tyler Baicar <[email protected]> --- arch/arm64/mm/fault.c | 31 +++++++++++++++++++++++++++---- 1 file changed, 27 insertions(+), 4 deletions(-) diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 156169c..50857f9 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -30,6 +30,7 @@ #include <linux/highmem.h> #include <linux/perf_event.h> #include <linux/preempt.h> +#include <linux/hugetlb.h> #include <asm/bug.h> #include <asm/cpufeature.h> @@ -193,9 +194,10 @@ static void __do_kernel_fault(struct mm_struct *mm, unsigned long addr, */ static void __do_user_fault(struct task_struct *tsk, unsigned long addr, unsigned int esr, unsigned int sig, int code, - struct pt_regs *regs) + struct pt_regs *regs, int fault) { struct siginfo si; + unsigned lsb = 0; if (unhandled_signal(tsk, sig) && show_unhandled_signals_ratelimited()) { pr_info("%s[%d]: unhandled %s (%d) at 0x%08lx, esr 0x%03x\n", @@ -211,6 +213,17 @@ static void __do_user_fault(struct task_struct *tsk, unsigned long addr, si.si_errno = 0; si.si_code = code; si.si_addr = (void __user *)addr; + /* + * 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; + si.si_addr_lsb = lsb; + force_sig_info(sig, &si, tsk); } @@ -224,7 +237,7 @@ static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *re * handle this fault with. */ if (user_mode(regs)) - __do_user_fault(tsk, addr, esr, SIGSEGV, SEGV_MAPERR, regs); + __do_user_fault(tsk, addr, esr, SIGSEGV, SEGV_MAPERR, regs, 0); else __do_kernel_fault(mm, addr, esr, regs); } @@ -426,7 +439,17 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr, */ sig = SIGBUS; code = BUS_ADRERR; - } else { + } +#ifdef CONFIG_MEMORY_FAILURE + else if (fault & (VM_FAULT_HWPOISON|VM_FAULT_HWPOISON_LARGE)) { + pr_err( + "Killing %s:%d due to hardware memory corruption fault at %lx\n", + tsk->comm, tsk->pid, addr); + sig = SIGBUS; + code = BUS_MCEERR_AR; + } +#endif + else { /* * Something tried to access memory that isn't in our memory * map. @@ -436,7 +459,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr, SEGV_ACCERR : SEGV_MAPERR; } - __do_user_fault(tsk, addr, esr, sig, code, regs); + __do_user_fault(tsk, addr, esr, sig, code, regs, fault); return 0; no_context: -- Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
