From e7c600f149b89e06073ab50f4f12e79828d3d2f0 Mon Sep 17 00:00:00 2001 From: "Jonathan (Zhixiong) Zhang" Date: Thu, 8 Jun 2017 18:25:27 +0100 Subject: [PATCH] arm64: hwpoison: add VM_FAULT_HWPOISON[_LARGE] handling 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 Signed-off-by: Tyler Baicar (fix new __do_user_fault call-site) Signed-off-by: Punit Agrawal Acked-by: Steve Capper Tested-by: Manoj Iyer Signed-off-by: Will Deacon --- arch/arm64/mm/fault.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-) diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 222427ae23d6..d73e7f1fe184 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include @@ -256,10 +257,11 @@ static void __do_kernel_fault(unsigned long addr, unsigned int esr, */ 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; const struct fault_info *inf; + unsigned int lsb = 0; if (unhandled_signal(tsk, sig) && show_unhandled_signals_ratelimited()) { inf = esr_to_fault_info(esr); @@ -277,6 +279,17 @@ 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); } @@ -291,7 +304,7 @@ static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *re */ if (user_mode(regs)) { inf = esr_to_fault_info(esr); - __do_user_fault(tsk, addr, esr, inf->sig, inf->code, regs); + __do_user_fault(tsk, addr, esr, inf->sig, inf->code, regs, 0); } else __do_kernel_fault(addr, esr, regs); } @@ -478,6 +491,9 @@ retry: */ sig = SIGBUS; code = BUS_ADRERR; + } else if (fault & (VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE)) { + sig = SIGBUS; + code = BUS_MCEERR_AR; } else { /* * Something tried to access memory that isn't in our memory @@ -488,7 +504,7 @@ retry: 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: -- 2.20.1