LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Toshi Kani <toshi.kani@hpe.com>
To: mhocko@suse.com, akpm@linux-foundation.org, tglx@linutronix.de,
	mingo@redhat.com, hpa@zytor.com, bp@suse.de,
	catalin.marinas@arm.com
Cc: guohanjun@huawei.com, will.deacon@arm.com,
	wxf.wang@hisilicon.com, willy@infradead.org,
	cpandya@codeaurora.org, linux-mm@kvack.org, x86@kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, Toshi Kani <toshi.kani@hpe.com>,
	stable@vger.kernel.org
Subject: [PATCH v2 2/2] x86/mm: implement free pmd/pte page interfaces
Date: Wed, 14 Mar 2018 12:01:55 -0600	[thread overview]
Message-ID: <20180314180155.19492-3-toshi.kani@hpe.com> (raw)
In-Reply-To: <20180314180155.19492-1-toshi.kani@hpe.com>

Implement pud_free_pmd_page() and pmd_free_pte_page() on x86, which
clear a given pud/pmd entry and free up lower level page table(s).
Address range associated with the pud/pmd entry must have been purged
by INVLPG.

fixes: e61ce6ade404e ("mm: change ioremap to set up huge I/O mappings")
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org>
---
 arch/x86/mm/pgtable.c |   28 ++++++++++++++++++++++++++--
 1 file changed, 26 insertions(+), 2 deletions(-)

diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index 1eed7ed518e6..34cda7e0551b 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -712,7 +712,22 @@ int pmd_clear_huge(pmd_t *pmd)
  */
 int pud_free_pmd_page(pud_t *pud)
 {
-	return pud_none(*pud);
+	pmd_t *pmd;
+	int i;
+
+	if (pud_none(*pud))
+		return 1;
+
+	pmd = (pmd_t *)pud_page_vaddr(*pud);
+
+	for (i = 0; i < PTRS_PER_PMD; i++)
+		if (!pmd_free_pte_page(&pmd[i]))
+			return 0;
+
+	pud_clear(pud);
+	free_page((unsigned long)pmd);
+
+	return 1;
 }
 
 /**
@@ -724,6 +739,15 @@ int pud_free_pmd_page(pud_t *pud)
  */
 int pmd_free_pte_page(pmd_t *pmd)
 {
-	return pmd_none(*pmd);
+	pte_t *pte;
+
+	if (pmd_none(*pmd))
+		return 1;
+
+	pte = (pte_t *)pmd_page_vaddr(*pmd);
+	pmd_clear(pmd);
+	free_page((unsigned long)pte);
+
+	return 1;
 }
 #endif	/* CONFIG_HAVE_ARCH_HUGE_VMAP */

  parent reply	other threads:[~2018-03-14 18:11 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-03-14 18:01 [PATCH v2 0/2] fix memory leak / panic in ioremap huge pages Toshi Kani
2018-03-14 18:01 ` [PATCH v2 1/2] mm/vmalloc: Add interfaces to free unmapped page table Toshi Kani
2018-03-14 22:38   ` Andrew Morton
2018-03-15 14:27     ` Kani, Toshi
2018-03-14 18:01 ` Toshi Kani [this message]
2018-03-15  7:39   ` [PATCH v2 2/2] x86/mm: implement free pmd/pte page interfaces Chintan Pandya
2018-03-15 14:51     ` Kani, Toshi
2018-04-26 14:19   ` Joerg Roedel
2018-04-26 16:21     ` Kani, Toshi
2018-04-26 17:23       ` joro
2018-04-26 17:49         ` Kani, Toshi
2018-04-26 20:07           ` joro
2018-04-26 22:30             ` Kani, Toshi
2018-04-27  7:37               ` joro
2018-04-27 11:39                 ` Michal Hocko
2018-04-27 11:46                   ` joro
2018-04-27 11:52                 ` Chintan Pandya
2018-04-27 12:48                   ` joro
2018-04-27 13:42                     ` Chintan Pandya
2018-04-27 14:31                 ` Kani, Toshi
2018-04-28  9:02                   ` joro
2018-04-28 20:54                     ` Kani, Toshi
2018-04-30  7:30                       ` Chintan Pandya
2018-04-30 13:43                         ` Kani, Toshi

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=20180314180155.19492-3-toshi.kani@hpe.com \
    --to=toshi.kani@hpe.com \
    --cc=akpm@linux-foundation.org \
    --cc=bp@suse.de \
    --cc=catalin.marinas@arm.com \
    --cc=cpandya@codeaurora.org \
    --cc=guohanjun@huawei.com \
    --cc=hpa@zytor.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mhocko@suse.com \
    --cc=mingo@redhat.com \
    --cc=stable@vger.kernel.org \
    --cc=tglx@linutronix.de \
    --cc=will.deacon@arm.com \
    --cc=willy@infradead.org \
    --cc=wxf.wang@hisilicon.com \
    --cc=x86@kernel.org \
    --subject='Re: [PATCH v2 2/2] x86/mm: implement free pmd/pte page interfaces' \
    /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

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).