From: Jia He <justin.he@arm•com>
To: Catalin Marinas <catalin.marinas@arm•com>,
Will Deacon <will@kernel•org>,
Mark Rutland <mark.rutland@arm•com>,
James Morse <james.morse@arm•com>, Marc Zyngier <maz@kernel•org>,
Matthew Wilcox <willy@infradead•org>,
"Kirill A. Shutemov" <kirill.shutemov@linux•intel.com>,
linux-arm-kernel@lists•infradead.org,
linux-kernel@vger•kernel.org, linux-mm@kvack•org
Cc: Jia He <justin.he@arm•com>, Kaly Xin <Kaly.Xin@arm•com>,
Punit Agrawal <punitagrawal@gmail•com>,
hejianet@gmail•com, Thomas Gleixner <tglx@linutronix•de>,
Andrew Morton <akpm@linux-foundation•org>
Subject: [PATCH v10 0/3] fix double page fault on arm64
Date: Mon, 30 Sep 2019 09:57:37 +0800 [thread overview]
Message-ID: <20190930015740.84362-1-justin.he@arm.com> (raw)
When we tested pmdk unit test vmmalloc_fork TEST1 in arm64 guest, there
will be a double page fault in __copy_from_user_inatomic of cow_user_page.
As told by Catalin: "On arm64 without hardware Access Flag, copying from
user will fail because the pte is old and cannot be marked young. So we
always end up with zeroed page after fork() + CoW for pfn mappings. we
don't always have a hardware-managed access flag on arm64."
Changes
v10:
add r-b from Catalin and a-b from Kirill in PATCH 03
remoe Reported-by in PATCH 01
v9: refactor cow_user_page for indention optimization (Catalin)
hold the ptl longer (Catalin)
v8: change cow_user_page's return type (Matthew)
v7: s/pte_spinlock/pte_offset_map_lock (Kirill)
v6: fix error case of returning with spinlock taken (Catalin)
move kmap_atomic to avoid handling kunmap_atomic
v5: handle the case correctly when !pte_same
fix kbuild test failed
v4: introduce cpu_has_hw_af (Suzuki)
bail out if !pte_same (Kirill)
v3: add vmf->ptl lock/unlock (Kirill A. Shutemov)
add arch_faults_on_old_pte (Matthew, Catalin)
v2: remove FAULT_FLAG_WRITE when setting pte access flag (Catalin)
Jia He (3):
arm64: cpufeature: introduce helper cpu_has_hw_af()
arm64: mm: implement arch_faults_on_old_pte() on arm64
mm: fix double page fault on arm64 if PTE_AF is cleared
arch/arm64/include/asm/cpufeature.h | 10 +++
arch/arm64/include/asm/pgtable.h | 14 ++++
mm/memory.c | 99 ++++++++++++++++++++++++-----
3 files changed, 108 insertions(+), 15 deletions(-)
--
2.17.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists•infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next reply other threads:[~2019-09-30 1:58 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-30 1:57 Jia He [this message]
2019-09-30 1:57 ` [PATCH v10 1/3] arm64: cpufeature: introduce helper cpu_has_hw_af() Jia He
2019-10-01 12:54 ` Will Deacon
2019-10-01 13:18 ` Marc Zyngier
2019-10-08 1:12 ` Justin He (Arm Technology China)
2019-10-08 15:32 ` Suzuki K Poulose
2019-10-09 6:29 ` Jia He
2019-09-30 1:57 ` [PATCH v10 2/3] arm64: mm: implement arch_faults_on_old_pte() on arm64 Jia He
2019-10-01 12:50 ` Will Deacon
2019-10-01 13:32 ` Marc Zyngier
2019-10-08 1:55 ` Justin He (Arm Technology China)
2019-10-08 2:30 ` Justin He (Arm Technology China)
2019-10-08 7:46 ` Marc Zyngier
2019-09-30 1:57 ` [PATCH v10 3/3] mm: fix double page fault on arm64 if PTE_AF is cleared Jia He
2019-10-01 12:54 ` Will Deacon
2019-10-08 2:19 ` Justin He (Arm Technology China)
2019-10-08 12:39 ` Will Deacon
2019-10-08 12:58 ` Justin He (Arm Technology China)
2019-10-08 14:32 ` Kirill A. Shutemov
2019-10-16 23:21 ` Palmer Dabbelt
2019-10-16 23:46 ` Will Deacon
2019-10-18 20:38 ` Palmer Dabbelt
2019-10-19 2:59 ` Jia He
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=20190930015740.84362-1-justin.he@arm.com \
--to=justin.he@arm$(echo .)com \
--cc=Kaly.Xin@arm$(echo .)com \
--cc=akpm@linux-foundation$(echo .)org \
--cc=catalin.marinas@arm$(echo .)com \
--cc=hejianet@gmail$(echo .)com \
--cc=james.morse@arm$(echo .)com \
--cc=kirill.shutemov@linux$(echo .)intel.com \
--cc=linux-arm-kernel@lists$(echo .)infradead.org \
--cc=linux-kernel@vger$(echo .)kernel.org \
--cc=linux-mm@kvack$(echo .)org \
--cc=mark.rutland@arm$(echo .)com \
--cc=maz@kernel$(echo .)org \
--cc=punitagrawal@gmail$(echo .)com \
--cc=tglx@linutronix$(echo .)de \
--cc=will@kernel$(echo .)org \
--cc=willy@infradead$(echo .)org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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