FAILED: patch "[PATCH] powerpc/64s/radix: Fix soft dirty tracking" failed to apply to 4.14-stable tree

FAILED: patch "[PATCH] powerpc/64s/radix: Fix soft dirty tracking" failed to apply to 4.14-stable tree

[gregkh]

The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.14.y
git checkout FETCH_HEAD
git cherry-pick -x 66b2ca086210732954a7790d63d35542936fc664
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2023052253-oppressed-blurb-418a@gregkh' --subject-prefix 'PATCH 4.14.y' HEAD^..

Possible dependencies:

66b2ca086210 ("powerpc/64s/radix: Fix soft dirty tracking")
47d99948eee4 ("powerpc/mm: Move book3s64 specifics in subdirectory mm/book3s64")
fb0b0a73b223 ("powerpc: Enable kcov")
e66c3209c7fd ("powerpc: Move page table dump files in a dedicated subdirectory")
7c91efce1608 ("powerpc/mm: dump block address translation on book3s/32")
0261a508c9fc ("powerpc/mm: dump segment registers on book3s/32")
32ea4c149990 ("powerpc/mm: Extend pte_fragment functionality to PPC32")
a74791dd9833 ("powerpc/mm: add helpers to get/set mm.context->pte_frag")
d09780f3a8d4 ("powerpc/mm: Move pgtable_t into platform headers")
994da93d1968 ("powerpc/mm: move platform specific mmu-xxx.h in platform directories")
a95d133c8643 ("powerpc/mm: Move pte_fragment_alloc() to a common location")
a43ccc4bc499 ("powerpc/book3s32: Remove CONFIG_BOOKE dependent code")
5b3e84fc10dd ("powerpc: change CONFIG_PPC_STD_MMU to CONFIG_PPC_BOOK3S")
68289ae935da ("powerpc: change CONFIG_PPC_STD_MMU_32 to CONFIG_PPC_BOOK3S_32")
9a8dd708d547 ("memblock: rename memblock_alloc{_nid,_try_nid} to memblock_phys_alloc*")
48e7b7695745 ("powerpc/64s/hash: Convert SLB miss handlers to C")
97026b5a5ac2 ("powerpc/mm: Split dump_pagelinuxtables flag_array table")
34eb138ed74d ("powerpc/mm: don't use _PAGE_EXEC for calling hash_preload()")
c766ee72235d ("powerpc: handover page flags with a pgprot_t parameter")
56f3c1413f5c ("powerpc/mm: properly set PAGE_KERNEL flags in ioremap()")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 66b2ca086210732954a7790d63d35542936fc664 Mon Sep 17 00:00:00 2001
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Thu, 11 May 2023 21:42:24 +1000
Subject: [PATCH] powerpc/64s/radix: Fix soft dirty tracking
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

It was reported that soft dirty tracking doesn't work when using the
Radix MMU.

The tracking is supposed to work by clearing the soft dirty bit for a
mapping and then write protecting the PTE. If/when the page is written
to, a page fault occurs and the soft dirty bit is added back via
pte_mkdirty(). For example in wp_page_reuse():

	entry = maybe_mkwrite(pte_mkdirty(entry), vma);
	if (ptep_set_access_flags(vma, vmf->address, vmf->pte, entry, 1))
		update_mmu_cache(vma, vmf->address, vmf->pte);

Unfortunately on radix _PAGE_SOFTDIRTY is being dropped by
radix__ptep_set_access_flags(), called from ptep_set_access_flags(),
meaning the soft dirty bit is not set even though the page has been
written to.

Fix it by adding _PAGE_SOFTDIRTY to the set of bits that are able to be
changed in radix__ptep_set_access_flags().

Fixes: b0b5e9b13047 ("powerpc/mm/radix: Add radix pte #defines")
Cc: stable@vger.kernel.org # v4.7+
Reported-by: Dan Horák <dan@danny.cz>
Link: https://lore.kernel.org/r/20230511095558.56663a50f86bdc4cd97700b7@danny.cz
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230511114224.977423-1-mpe@ellerman.id.au

diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index 26245aaf12b8..2297aa764ecd 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -1040,8 +1040,8 @@ void radix__ptep_set_access_flags(struct vm_area_struct *vma, pte_t *ptep,
 				  pte_t entry, unsigned long address, int psize)
 {
 	struct mm_struct *mm = vma->vm_mm;
-	unsigned long set = pte_val(entry) & (_PAGE_DIRTY | _PAGE_ACCESSED |
-					      _PAGE_RW | _PAGE_EXEC);
+	unsigned long set = pte_val(entry) & (_PAGE_DIRTY | _PAGE_SOFT_DIRTY |
+					      _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
 
 	unsigned long change = pte_val(entry) ^ pte_val(*ptep);
 	/*