Merge branches 'for-next/kvm-build-fix', 'for-next/va-refactor', 'for-next/lto',...

[sfrench/cifs-2.6.git] / arch / arm64 / mm / fault.c

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 94c99c1c19e3fb6913f57115fa96814d94cfe291..29a6b8c9e8309eed523063dc7eb2fd2d37ea832a 100644 (file)
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -40,7 +40,7 @@
 #include <asm/traps.h>
 
 struct fault_info {
-       int     (*fn)(unsigned long addr, unsigned int esr,
+       int     (*fn)(unsigned long far, unsigned int esr,
                      struct pt_regs *regs);
        int     sig;
        int     code;
@@ -262,7 +262,7 @@ static bool __kprobes is_spurious_el1_translation_fault(unsigned long addr,
        local_irq_save(flags);
        asm volatile("at s1e1r, %0" :: "r" (addr));
        isb();
-       par = read_sysreg(par_el1);
+       par = read_sysreg_par();
        local_irq_restore(flags);
 
        /*
@@ -385,8 +385,11 @@ static void set_thread_esr(unsigned long address, unsigned int esr)
        current->thread.fault_code = esr;
 }
 
-static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *regs)
+static void do_bad_area(unsigned long far, unsigned int esr,
+                       struct pt_regs *regs)
 {
+       unsigned long addr = untagged_addr(far);
+
        /*
         * If we are in kernel mode at this point, we have no context to
         * handle this fault with.
@@ -395,8 +398,7 @@ static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *re
                const struct fault_info *inf = esr_to_fault_info(esr);
 
                set_thread_esr(addr, esr);
-               arm64_force_sig_fault(inf->sig, inf->code, (void __user *)addr,
-                                     inf->name);
+               arm64_force_sig_fault(inf->sig, inf->code, far, inf->name);
        } else {
                __do_kernel_fault(addr, esr, regs);
        }
@@ -448,7 +450,7 @@ static bool is_write_abort(unsigned int esr)
        return (esr & ESR_ELx_WNR) && !(esr & ESR_ELx_CM);
 }
 
-static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
+static int __kprobes do_page_fault(unsigned long far, unsigned int esr,
                                   struct pt_regs *regs)
 {
        const struct fault_info *inf;
@@ -456,6 +458,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
        vm_fault_t fault;
        unsigned long vm_flags = VM_ACCESS_FLAGS;
        unsigned int mm_flags = FAULT_FLAG_DEFAULT;
+       unsigned long addr = untagged_addr(far);
 
        if (kprobe_page_fault(regs, esr))
                return 0;
@@ -567,8 +570,7 @@ retry:
                 * We had some memory, but were unable to successfully fix up
                 * this page fault.
                 */
-               arm64_force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)addr,
-                                     inf->name);
+               arm64_force_sig_fault(SIGBUS, BUS_ADRERR, far, inf->name);
        } else if (fault & (VM_FAULT_HWPOISON_LARGE | VM_FAULT_HWPOISON)) {
                unsigned int lsb;
 
@@ -576,8 +578,7 @@ retry:
                if (fault & VM_FAULT_HWPOISON_LARGE)
                        lsb = hstate_index_to_shift(VM_FAULT_GET_HINDEX(fault));
 
-               arm64_force_sig_mceerr(BUS_MCEERR_AR, (void __user *)addr, lsb,
-                                      inf->name);
+               arm64_force_sig_mceerr(BUS_MCEERR_AR, far, lsb, inf->name);
        } else {
                /*
                 * Something tried to access memory that isn't in our memory
@@ -585,8 +586,7 @@ retry:
                 */
                arm64_force_sig_fault(SIGSEGV,
                                      fault == VM_FAULT_BADACCESS ? SEGV_ACCERR : SEGV_MAPERR,
-                                     (void __user *)addr,
-                                     inf->name);
+                                     far, inf->name);
        }
 
        return 0;
@@ -596,33 +596,35 @@ no_context:
        return 0;
 }
 
-static int __kprobes do_translation_fault(unsigned long addr,
+static int __kprobes do_translation_fault(unsigned long far,
                                          unsigned int esr,
                                          struct pt_regs *regs)
 {
+       unsigned long addr = untagged_addr(far);
+
        if (is_ttbr0_addr(addr))
-               return do_page_fault(addr, esr, regs);
+               return do_page_fault(far, esr, regs);
 
-       do_bad_area(addr, esr, regs);
+       do_bad_area(far, esr, regs);
        return 0;
 }
 
-static int do_alignment_fault(unsigned long addr, unsigned int esr,
+static int do_alignment_fault(unsigned long far, unsigned int esr,
                              struct pt_regs *regs)
 {
-       do_bad_area(addr, esr, regs);
+       do_bad_area(far, esr, regs);
        return 0;
 }
 
-static int do_bad(unsigned long addr, unsigned int esr, struct pt_regs *regs)
+static int do_bad(unsigned long far, unsigned int esr, struct pt_regs *regs)
 {
        return 1; /* "fault" */
 }
 
-static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs)
+static int do_sea(unsigned long far, unsigned int esr, struct pt_regs *regs)
 {
        const struct fault_info *inf;
-       void __user *siaddr;
+       unsigned long siaddr;
 
        inf = esr_to_fault_info(esr);
 
@@ -634,19 +636,30 @@ static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs)
                return 0;
        }
 
-       if (esr & ESR_ELx_FnV)
-               siaddr = NULL;
-       else
-               siaddr  = (void __user *)addr;
+       if (esr & ESR_ELx_FnV) {
+               siaddr = 0;
+       } else {
+               /*
+                * The architecture specifies that the tag bits of FAR_EL1 are
+                * UNKNOWN for synchronous external aborts. Mask them out now
+                * so that userspace doesn't see them.
+                */
+               siaddr  = untagged_addr(far);
+       }
        arm64_notify_die(inf->name, regs, inf->sig, inf->code, siaddr, esr);
 
        return 0;
 }
 
-static int do_tag_check_fault(unsigned long addr, unsigned int esr,
+static int do_tag_check_fault(unsigned long far, unsigned int esr,
                              struct pt_regs *regs)
 {
-       do_bad_area(addr, esr, regs);
+       /*
+        * The architecture specifies that bits 63:60 of FAR_EL1 are UNKNOWN for tag
+        * check faults. Mask them out now so that userspace doesn't see them.
+        */
+       far &= (1UL << 60) - 1;
+       do_bad_area(far, esr, regs);
        return 0;
 }
 
@@ -717,11 +730,12 @@ static const struct fault_info fault_info[] = {
        { do_bad,               SIGKILL, SI_KERNEL,     "unknown 63"                    },
 };
 
-void do_mem_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs)
+void do_mem_abort(unsigned long far, unsigned int esr, struct pt_regs *regs)
 {
        const struct fault_info *inf = esr_to_fault_info(esr);
+       unsigned long addr = untagged_addr(far);
 
-       if (!inf->fn(addr, esr, regs))
+       if (!inf->fn(far, esr, regs))
                return;
 
        if (!user_mode(regs)) {
@@ -730,8 +744,12 @@ void do_mem_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs)
                show_pte(addr);
        }
 
-       arm64_notify_die(inf->name, regs,
-                        inf->sig, inf->code, (void __user *)addr, esr);
+       /*
+        * At this point we have an unrecognized fault type whose tag bits may
+        * have been defined as UNKNOWN. Therefore we only expose the untagged
+        * address to the signal handler.
+        */
+       arm64_notify_die(inf->name, regs, inf->sig, inf->code, addr, esr);
 }
 NOKPROBE_SYMBOL(do_mem_abort);
 
@@ -744,8 +762,8 @@ NOKPROBE_SYMBOL(do_el0_irq_bp_hardening);
 
 void do_sp_pc_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 {
-       arm64_notify_die("SP/PC alignment exception", regs,
-                        SIGBUS, BUS_ADRALN, (void __user *)addr, esr);
+       arm64_notify_die("SP/PC alignment exception", regs, SIGBUS, BUS_ADRALN,
+                        addr, esr);
 }
 NOKPROBE_SYMBOL(do_sp_pc_abort);
 
@@ -871,8 +889,7 @@ void do_debug_exception(unsigned long addr_if_watchpoint, unsigned int esr,
                arm64_apply_bp_hardening();
 
        if (inf->fn(addr_if_watchpoint, esr, regs)) {
-               arm64_notify_die(inf->name, regs,
-                                inf->sig, inf->code, (void __user *)pc, esr);
+               arm64_notify_die(inf->name, regs, inf->sig, inf->code, pc, esr);
        }
 
        debug_exception_exit(regs);