Merge tag 'powerpc-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "A pretty small batch for us, and apologies for it being a bit late, I
  wanted to sneak Christophe's user_access_begin() series in.

  Summary:

   - Implement user_access_begin() and friends for our platforms that
     support controlling kernel access to userspace.

   - Enable CONFIG_VMAP_STACK on 32-bit Book3S and 8xx.

   - Some tweaks to our pseries IOMMU code to allow SVMs ("secure"
     virtual machines) to use the IOMMU.

   - Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE to the 32-bit
     VDSO, and some other improvements.

   - A series to use the PCI hotplug framework to control opencapi
     card's so that they can be reset and re-read after flashing a new
     FPGA image.

  As well as other minor fixes and improvements as usual.

  Thanks to: Alastair D'Silva, Alexandre Ghiti, Alexey Kardashevskiy,
  Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Bai Yingjie, Chen
  Zhou, Christophe Leroy, Frederic Barrat, Greg Kurz, Jason A.
  Donenfeld, Joel Stanley, Jordan Niethe, Julia Lawall, Krzysztof
  Kozlowski, Laurent Dufour, Laurentiu Tudor, Linus Walleij, Michael
  Bringmann, Nathan Chancellor, Nicholas Piggin, Nick Desaulniers,
  Oliver O'Halloran, Peter Ujfalusi, Pingfan Liu, Ram Pai, Randy Dunlap,
  Russell Currey, Sam Bobroff, Sebastian Andrzej Siewior, Shawn
  Anastasio, Stephen Rothwell, Steve Best, Sukadev Bhattiprolu, Thiago
  Jung Bauermann, Tyrel Datwyler, Vaibhav Jain"

* tag 'powerpc-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (131 commits)
  powerpc: configs: Cleanup old Kconfig options
  powerpc/configs/skiroot: Enable some more hardening options
  powerpc/configs/skiroot: Disable xmon default & enable reboot on panic
  powerpc/configs/skiroot: Enable security features
  powerpc/configs/skiroot: Update for symbol movement only
  powerpc/configs/skiroot: Drop default n CONFIG_CRYPTO_ECHAINIV
  powerpc/configs/skiroot: Drop HID_LOGITECH
  powerpc/configs: Drop NET_VENDOR_HP which moved to staging
  powerpc/configs: NET_CADENCE became NET_VENDOR_CADENCE
  powerpc/configs: Drop CONFIG_QLGE which moved to staging
  powerpc: Do not consider weak unresolved symbol relocations as bad
  powerpc/32s: Fix kasan_early_hash_table() for CONFIG_VMAP_STACK
  powerpc: indent to improve Kconfig readability
  powerpc: Provide initial documentation for PAPR hcalls
  powerpc: Implement user_access_save() and user_access_restore()
  powerpc: Implement user_access_begin and friends
  powerpc/32s: Prepare prevent_user_access() for user_access_end()
  powerpc/32s: Drop NULL addr verification
  powerpc/kuap: Fix set direction in allow/prevent_user_access()
  powerpc/32s: Fix bad_kuap_fault()
  ...

1 files changed, 2 insertions, 12 deletions

diff --git a/arch/powerpc/oprofile/backtrace.c b/arch/powerpc/oprofile/backtrace.c
index 6ffcb80cf844..6f347fa29f41 100644
--- a/arch/powerpc/oprofile/backtrace.c
+++ b/arch/powerpc/oprofile/backtrace.c
@@ -28,15 +28,12 @@ static unsigned int user_getsp32(unsigned int sp, int is_first)
 	unsigned int stack_frame[2];
 	void __user *p = compat_ptr(sp);
 
-	if (!access_ok(p, sizeof(stack_frame)))
-		return 0;
-
 	/*
 	 * The most likely reason for this is that we returned -EFAULT,
 	 * which means that we've done all that we can do from
 	 * interrupt context.
 	 */
-	if (__copy_from_user_inatomic(stack_frame, p, sizeof(stack_frame)))
+	if (probe_user_read(stack_frame, (void __user *)p, sizeof(stack_frame)))
 		return 0;
 
 	if (!is_first)
@@ -54,11 +51,7 @@ static unsigned long user_getsp64(unsigned long sp, int is_first)
 {
 	unsigned long stack_frame[3];
 
-	if (!access_ok((void __user *)sp, sizeof(stack_frame)))
-		return 0;
-
-	if (__copy_from_user_inatomic(stack_frame, (void __user *)sp,
-					sizeof(stack_frame)))
+	if (probe_user_read(stack_frame, (void __user *)sp, sizeof(stack_frame)))
 		return 0;
 
 	if (!is_first)
@@ -103,7 +96,6 @@ void op_powerpc_backtrace(struct pt_regs * const regs, unsigned int depth)
 			first_frame = 0;
 		}
 	} else {
-		pagefault_disable();
 #ifdef CONFIG_PPC64
 		if (!is_32bit_task()) {
 			while (depth--) {
@@ -112,7 +104,6 @@ void op_powerpc_backtrace(struct pt_regs * const regs, unsigned int depth)
 					break;
 				first_frame = 0;
 			}
-			pagefault_enable();
 			return;
 		}
 #endif
@@ -123,6 +114,5 @@ void op_powerpc_backtrace(struct pt_regs * const regs, unsigned int depth)
 				break;
 			first_frame = 0;
 		}
-		pagefault_enable();
 	}
 }