1 files changed, 45 insertions, 57 deletions

diff --git a/arch/sparc/mm/fault_64.c b/arch/sparc/mm/fault_64.c
index b84c4dd14954..e326caf708c6 100644
--- a/arch/sparc/mm/fault_64.c
+++ b/arch/sparc/mm/fault_64.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * arch/sparc64/mm/fault.c: Page fault handlers for the 64-bit Sparc.
  *
@@ -26,7 +27,6 @@
 #include <linux/uaccess.h>
 
 #include <asm/page.h>
-#include <asm/pgtable.h>
 #include <asm/openprom.h>
 #include <asm/oplib.h>
 #include <asm/asi.h>
@@ -37,20 +37,6 @@
 
 int show_unhandled_signals = 1;
 
-static inline __kprobes int notify_page_fault(struct pt_regs *regs)
-{
-	int ret = 0;
-
-	/* kprobe_running() needs smp_processor_id() */
-	if (kprobes_built_in() && !user_mode(regs)) {
-		preempt_disable();
-		if (kprobe_running() && kprobe_fault_handler(regs, 0))
-			ret = 1;
-		preempt_enable();
-	}
-	return ret;
-}
-
 static void __kprobes unhandled_fault(unsigned long address,
 				      struct task_struct *tsk,
 				      struct pt_regs *regs)
@@ -84,7 +70,7 @@ static void __kprobes bad_kernel_pc(struct pt_regs *regs, unsigned long vaddr)
 }
 
 /*
- * We now make sure that mmap_sem is held in all paths that call 
+ * We now make sure that mmap_lock is held in all paths that call
  * this. Additionally, to prevent kswapd from ripping ptes from
  * under us, raise interrupts around the time that we look at the
  * pte, kswapd will have to wait to get his smp ipi response from
@@ -93,6 +79,7 @@ static void __kprobes bad_kernel_pc(struct pt_regs *regs, unsigned long vaddr)
 static unsigned int get_user_insn(unsigned long tpc)
 {
 	pgd_t *pgdp = pgd_offset(current->mm, tpc);
+	p4d_t *p4dp;
 	pud_t *pudp;
 	pmd_t *pmdp;
 	pte_t *ptep, pte;
@@ -101,7 +88,10 @@ static unsigned int get_user_insn(unsigned long tpc)
 
 	if (pgd_none(*pgdp) || unlikely(pgd_bad(*pgdp)))
 		goto out;
-	pudp = pud_offset(pgdp, tpc);
+	p4dp = p4d_offset(pgdp, tpc);
+	if (p4d_none(*p4dp) || unlikely(p4d_bad(*p4dp)))
+		goto out;
+	pudp = pud_offset(p4dp, tpc);
 	if (pud_none(*pudp) || unlikely(pud_bad(*pudp)))
 		goto out;
 
@@ -109,6 +99,7 @@ static unsigned int get_user_insn(unsigned long tpc)
 	local_irq_disable();
 
 	pmdp = pmd_offset(pudp, tpc);
+again:
 	if (pmd_none(*pmdp) || unlikely(pmd_bad(*pmdp)))
 		goto out_irq_enable;
 
@@ -125,6 +116,8 @@ static unsigned int get_user_insn(unsigned long tpc)
 #endif
 	{
 		ptep = pte_offset_map(pmdp, tpc);
+		if (!ptep)
+			goto again;
 		pte = *ptep;
 		if (pte_present(pte)) {
 			pa  = (pte_pfn(pte) << PAGE_SHIFT);
@@ -153,7 +146,7 @@ show_signal_msg(struct pt_regs *regs, int sig, int code,
 	if (!printk_ratelimit())
 		return;
 
-	printk("%s%s[%d]: segfault at %lx ip %p (rpc %p) sp %p error %x",
+	printk("%s%s[%d]: segfault at %lx ip %px (rpc %px) sp %px error %x",
 	       task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
 	       tsk->comm, task_pid_nr(tsk), address,
 	       (void *)regs->tpc, (void *)regs->u_regs[UREG_I7],
@@ -169,11 +162,7 @@ static void do_fault_siginfo(int code, int sig, struct pt_regs *regs,
 			     int fault_code)
 {
 	unsigned long addr;
-	siginfo_t info;
 
-	info.si_code = code;
-	info.si_signo = sig;
-	info.si_errno = 0;
 	if (fault_code & FAULT_CODE_ITLB) {
 		addr = regs->tpc;
 	} else {
@@ -186,13 +175,11 @@ static void do_fault_siginfo(int code, int sig, struct pt_regs *regs,
 		else
 			addr = fault_addr;
 	}
-	info.si_addr = (void __user *) addr;
-	info.si_trapno = 0;
 
 	if (unlikely(show_unhandled_signals))
 		show_signal_msg(regs, sig, code, addr, current);
 
-	force_sig_info(sig, &info, current);
+	force_sig_fault(sig, code, (void __user *) addr);
 }
 
 static unsigned int get_fault_insn(struct pt_regs *regs, unsigned int insn)
@@ -283,13 +270,14 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
 	struct mm_struct *mm = current->mm;
 	struct vm_area_struct *vma;
 	unsigned int insn = 0;
-	int si_code, fault_code, fault;
+	int si_code, fault_code;
+	vm_fault_t fault;
 	unsigned long address, mm_rss;
-	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+	unsigned int flags = FAULT_FLAG_DEFAULT;
 
 	fault_code = get_thread_fault_code();
 
-	if (notify_page_fault(regs))
+	if (kprobe_page_fault(regs, 0))
 		goto exit_exception;
 
 	si_code = SEGV_MAPERR;
@@ -333,7 +321,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
 
 	perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 
-	if (!down_read_trylock(&mm->mmap_sem)) {
+	if (!mmap_read_trylock(mm)) {
 		if ((regs->tstate & TSTATE_PRIV) &&
 		    !search_exception_tables(regs->tpc)) {
 			insn = get_fault_insn(regs, insn);
@@ -341,7 +329,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
 		}
 
 retry:
-		down_read(&mm->mmap_sem);
+		mmap_read_lock(mm);
 	}
 
 	if (fault_code & FAULT_CODE_BAD_RA)
@@ -398,8 +386,9 @@ continue_fault:
 				goto bad_area;
 		}
 	}
-	if (expand_stack(vma, address))
-		goto bad_area;
+	vma = expand_stack(mm, address);
+	if (!vma)
+		goto bad_area_nosemaphore;
 	/*
 	 * Ok, we have a good vm_area for this memory access, so
 	 * we can handle it..
@@ -437,10 +426,19 @@ good_area:
 			goto bad_area;
 	}
 
-	fault = handle_mm_fault(vma, address, flags);
+	fault = handle_mm_fault(vma, address, flags, regs);
 
-	if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current))
+	if (fault_signal_pending(fault, regs)) {
+		if (regs->tstate & TSTATE_PRIV) {
+			insn = get_fault_insn(regs, insn);
+			goto handle_kernel_fault;
+		}
 		goto exit_exception;
+	}
+
+	/* The fault is fully completed (including releasing mmap lock) */
+	if (fault & VM_FAULT_COMPLETED)
+		goto lock_released;
 
 	if (unlikely(fault & VM_FAULT_ERROR)) {
 		if (fault & VM_FAULT_OOM)
@@ -452,30 +450,19 @@ good_area:
 		BUG();
 	}
 
-	if (flags & FAULT_FLAG_ALLOW_RETRY) {
-		if (fault & VM_FAULT_MAJOR) {
-			current->maj_flt++;
-			perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ,
-				      1, regs, address);
-		} else {
-			current->min_flt++;
-			perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN,
-				      1, regs, address);
-		}
-		if (fault & VM_FAULT_RETRY) {
-			flags &= ~FAULT_FLAG_ALLOW_RETRY;
-			flags |= FAULT_FLAG_TRIED;
+	if (fault & VM_FAULT_RETRY) {
+		flags |= FAULT_FLAG_TRIED;
 
-			/* No need to up_read(&mm->mmap_sem) as we would
-			 * have already released it in __lock_page_or_retry
-			 * in mm/filemap.c.
-			 */
+		/* No need to mmap_read_unlock(mm) as we would
+		 * have already released it in __lock_page_or_retry
+		 * in mm/filemap.c.
+		 */
 
-			goto retry;
-		}
+		goto retry;
 	}
-	up_read(&mm->mmap_sem);
+	mmap_read_unlock(mm);
 
+lock_released:
 	mm_rss = get_mm_rss(mm);
 #if defined(CONFIG_TRANSPARENT_HUGEPAGE)
 	mm_rss -= (mm->context.thp_pte_count * (HPAGE_SIZE / PAGE_SIZE));
@@ -504,8 +491,9 @@ exit_exception:
 	 * Fix it, but check if it's kernel or user first..
 	 */
 bad_area:
+	mmap_read_unlock(mm);
+bad_area_nosemaphore:
 	insn = get_fault_insn(regs, insn);
-	up_read(&mm->mmap_sem);
 
 handle_kernel_fault:
 	do_kernel_fault(regs, si_code, fault_code, insn, address);
@@ -517,7 +505,7 @@ handle_kernel_fault:
  */
 out_of_memory:
 	insn = get_fault_insn(regs, insn);
-	up_read(&mm->mmap_sem);
+	mmap_read_unlock(mm);
 	if (!(regs->tstate & TSTATE_PRIV)) {
 		pagefault_out_of_memory();
 		goto exit_exception;
@@ -530,7 +518,7 @@ intr_or_no_mm:
 
 do_sigbus:
 	insn = get_fault_insn(regs, insn);
-	up_read(&mm->mmap_sem);
+	mmap_read_unlock(mm);
 
 	/*
 	 * Send a sigbus, regardless of whether we were in kernel