linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed
From: Nicholas Piggin <npiggin@gmail.com>
To: linuxppc-dev@lists.ozlabs.org
Cc: Nicholas Piggin <npiggin@gmail.com>
Subject: [PATCH] powerpc/64s/radix: Fix unmapping huge vmaps when CONFIG_HUGETLB_PAGE=n
Date: Fri, 26 Nov 2021 12:28:34 +1000	[thread overview]
Message-ID: <20211126022834.1622106-1-npiggin@gmail.com> (raw)

pmd_huge is defined out to false when HUGETLB_PAGE is not configured,
but the vmap code still installs huge PMDs. This leads to errors
encountering bad PMDs when vunmapping because it is not seen as a
huge PTE, and the bad PMD check catches it. The end result may not
be much more serious than some bad pmd warning messages, because the
pmd_none_or_clear_bad() does what we wanted and clears the huge PTE
anyway.

Fix this by checking pmd_is_leaf(), which checks for a PTE regardless
of config options. The whole huge/large/leaf stuff is a tangled mess
but that's kernel-wide and not something we can improve much in
arch/powerpc code.

Fixes: d909f9109c30 ("powerpc/64s/radix: Enable HAVE_ARCH_HUGE_VMAP")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/mm/book3s64/radix_pgtable.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index 99dbee114539..7559638068ef 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -1089,7 +1089,7 @@ int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)
 
 int pud_clear_huge(pud_t *pud)
 {
-	if (pud_huge(*pud)) {
+	if (pud_is_leaf(*pud)) {
 		pud_clear(pud);
 		return 1;
 	}
@@ -1136,7 +1136,7 @@ int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot)
 
 int pmd_clear_huge(pmd_t *pmd)
 {
-	if (pmd_huge(*pmd)) {
+	if (pmd_is_leaf(*pmd)) {
 		pmd_clear(pmd);
 		return 1;
 	}
-- 
2.23.0


             reply	other threads:[~2021-11-26  2:29 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-26  2:28 Nicholas Piggin [this message]
2021-11-26  6:09 ` [PATCH] powerpc/64s/radix: Fix unmapping huge vmaps when CONFIG_HUGETLB_PAGE=n Daniel Axtens
2021-11-26 10:55   ` Nicholas Piggin

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20211126022834.1622106-1-npiggin@gmail.com \
    --to=npiggin@gmail.com \
    --cc=linuxppc-dev@lists.ozlabs.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).