Patch "kaiser: drop is_atomic arg to kaiser_pagetable_walk()" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

kaiser: drop is_atomic arg to kaiser_pagetable_walk()

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
kaiser-drop-is_atomic-arg-to-kaiser_pagetable_walk.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Hugh Dickins <[email protected]>
Date: Sun, 29 Oct 2017 11:36:19 -0700
Subject: kaiser: drop is_atomic arg to kaiser_pagetable_walk()

From: Hugh Dickins <[email protected]>

I have not observed a might_sleep() warning from setup_fixmap_gdt()'s use of kaiser_add_mapping() in our tree (why not?), but like upstream we have not provided a way for that to pass is_atomic true down to kaiser_pagetable_walk(), and at startup it's far from a likely source of trouble: so just delete the walk's is_atomic arg and might_sleep().

---
 arch/x86/mm/kaiser.c |   10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

@@ -107,19 +107,13 @@ static inline unsigned long get_pa_from_
  *
  * Returns a pointer to a PTE on success, or NULL on failure.
  */
-static pte_t *kaiser_pagetable_walk(unsigned long address, bool is_atomic)
+static pte_t *kaiser_pagetable_walk(unsigned long address)
 {
 	pmd_t *pmd;
 	pud_t *pud;
 	pgd_t *pgd = native_get_shadow_pgd(pgd_offset_k(address));
 	gfp_t gfp = (GFP_KERNEL | __GFP_NOTRACK | __GFP_ZERO);
 
-	if (is_atomic) {
-		gfp &= ~GFP_KERNEL;
-		gfp |= __GFP_HIGH | __GFP_ATOMIC;
-	} else
-		might_sleep();
-
 	if (pgd_none(*pgd)) {
 		WARN_ONCE(1, "All shadow pgds should have been populated");
 		return NULL;

@@ -194,7 +188,7 @@ static int kaiser_add_user_map(const voi
 			ret = -EIO;
 			break;
 		}
-		pte = kaiser_pagetable_walk(address, false);
+		pte = kaiser_pagetable_walk(address);
 		if (!pte) {
 			ret = -ENOMEM;
 			break;

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/kaiser-vmstat-show-nr_kaisertable-as-nr_overhead.patch queue-4.9/kaiser-add-nokaiser-boot-option-using-alternative.patch queue-4.9/kaiser-fix-unlikely-error-in-alloc_ldt_struct.patch queue-4.9/kaiser-kaiser_flush_tlb_on_return_to_user-check-pcid.patch queue-4.9/x86-paravirt-dont-patch-flush_tlb_single.patch queue-4.9/kaiser-merged-update.patch queue-4.9/kaiser-delete-kaiser_real_switch-option.patch queue-4.9/kaiser-kaiser_remove_mapping-move-along-the-pgd.patch queue-4.9/kaiser-fix-perf-crashes.patch queue-4.9/kaiser-drop-is_atomic-arg-to-kaiser_pagetable_walk.patch queue-4.9/kaiser-load_new_mm_cr3-let-switch_user_cr3-flush-user.patch queue-4.9/kaiser-enhanced-by-kernel-and-user-pcids.patch queue-4.9/kaiser-x86_cr3_pcid_noflush-and-x86_cr3_pcid_user.patch queue-4.9/kaiser-align-addition-to-x86-mm-makefile.patch queue-4.9/kaiser-use-alternative-instead-of-x86_cr3_pcid_noflush.patch queue-4.9/kaiser-stack-map-page_size-at-thread_size-page_size.patch queue-4.9/kaiser-name-that-0x1000-kaiser_shadow_pgd_offset.patch queue-4.9/kaiser-fix-regs-to-do_nmi-ifndef-config_kaiser.patch queue-4.9/kaiser-do-not-set-_page_nx-on-pgd_none.patch queue-4.9/kaiser-tidied-up-asm-kaiser.h-somewhat.patch queue-4.9/kaiser-cleanups-while-trying-for-gold-link.patch queue-4.9/kaiser-tidied-up-kaiser_add-remove_mapping-slightly.patch queue-4.9/kaiser-fix-build-and-fixme-in-alloc_ldt_struct.patch queue-4.9/kaiser-kernel-address-isolation.patch queue-4.9/kaiser-enomem-if-kaiser_pagetable_walk-null.patch queue-4.9/kaiser-asm-tlbflush.h-handle-nopge-at-lower-level.patch queue-4.9/kaiser-paranoid_entry-pass-cr3-need-to-paranoid_exit.patch queue-4.9/kaiser-kaiser-depends-on-smp.patch queue-4.9/kaiser-pcid-0-for-kernel-and-128-for-user.patch