From: David Hildenbrand <david@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org, "Michal Hocko" <mhocko@kernel.org>,
"Andrew Morton" <akpm@linux-foundation.org>,
kvm-ppc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
kvm@vger.kernel.org, linux-hyperv@vger.kernel.org,
devel@driverdev.osuosl.org, xen-devel@lists.xenproject.org,
x86@kernel.org, "Alexander Duyck" <alexander.duyck@gmail.com>,
"Alexander Duyck" <alexander.h.duyck@linux.intel.com>,
"Alex Williamson" <alex.williamson@redhat.com>,
"Allison Randal" <allison@lohutok.net>,
"Andy Lutomirski" <luto@kernel.org>,
"Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>,
"Anshuman Khandual" <anshuman.khandual@arm.com>,
"Anthony Yznaga" <anthony.yznaga@oracle.com>,
"Ben Chan" <benchan@chromium.org>,
"Benjamin Herrenschmidt" <benh@kernel.crashing.org>,
"Borislav Petkov" <bp@alien8.de>,
"Boris Ostrovsky" <boris.ostrovsky@oracle.com>,
"Christophe Leroy" <christophe.leroy@c-s.fr>,
"Cornelia Huck" <cohuck@redhat.com>,
"Dan Carpenter" <dan.carpenter@oracle.com>,
"Dan Williams" <dan.j.williams@intel.com>,
"Dave Hansen" <dave.hansen@linux.intel.com>,
"Fabio Estevam" <festevam@gmail.com>,
"Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
"Haiyang Zhang" <haiyangz@microsoft.com>,
"H. Peter Anvin" <hpa@zytor.com>,
"Ingo Molnar" <mingo@redhat.com>,
"Isaac J. Manjarres" <isaacm@codeaurora.org>,
"Jeremy Sowden" <jeremy@azazel.net>,
"Jim Mattson" <jmattson@google.com>,
"Joerg Roedel" <joro@8bytes.org>,
"Johannes Weiner" <hannes@cmpxchg.org>,
"Juergen Gross" <jgross@suse.com>,
"KarimAllah Ahmed" <karahmed@amazon.de>,
"Kate Stewart" <kstewart@linuxfoundation.org>,
"Kees Cook" <keescook@chromium.org>,
"K. Y. Srinivasan" <kys@microsoft.com>,
"Madhumitha Prabakaran" <madhumithabiw@gmail.com>,
"Matt Sickler" <Matt.Sickler@daktronics.com>,
"Mel Gorman" <mgorman@techsingularity.net>,
"Michael Ellerman" <mpe@ellerman.id.au>,
"Michal Hocko" <mhocko@suse.com>,
"Mike Rapoport" <rppt@linux.ibm.com>,
"Mike Rapoport" <rppt@linux.vnet.ibm.com>,
"Nicholas Piggin" <npiggin@gmail.com>,
"Nishka Dasgupta" <nishkadg.linux@gmail.com>,
"Oscar Salvador" <osalvador@suse.de>,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Paul Mackerras" <paulus@ozlabs.org>,
"Paul Mackerras" <paulus@samba.org>,
"Pavel Tatashin" <pasha.tatashin@soleen.com>,
"Pavel Tatashin" <pavel.tatashin@microsoft.com>,
"Peter Zijlstra" <peterz@infradead.org>, "Qian Cai" <cai@lca.pw>,
"Radim Krčmář" <rkrcmar@redhat.com>,
"Rob Springer" <rspringer@google.com>,
"Sasha Levin" <sashal@kernel.org>,
"Sean Christopherson" <sean.j.christopherson@intel.com>,
"Simon Sandström" <simon@nikanor.nu>,
"Stefano Stabellini" <sstabellini@kernel.org>,
"Stephen Hemminger" <sthemmin@microsoft.com>,
"Thomas Gleixner" <tglx@linutronix.de>,
"Todd Poynor" <toddpoynor@google.com>,
"Vandana BN" <bnvandana@gmail.com>,
"Vitaly Kuznetsov" <vkuznets@redhat.com>,
"Vlastimil Babka" <vbabka@suse.cz>,
"Wanpeng Li" <wanpengli@tencent.com>,
YueHaibing <yuehaibing@huawei.com>
Subject: Re: [PATCH RFC v1 02/12] mm/usercopy.c: Prepare check_page_span() for PG_reserved changes
Date: Wed, 23 Oct 2019 10:20:14 +0200 [thread overview]
Message-ID: <a8313fb1-50f3-9083-fd07-297ddf86658e@redhat.com> (raw)
In-Reply-To: <20191022171239.21487-3-david@redhat.com>
On 22.10.19 19:12, David Hildenbrand wrote:
> Right now, ZONE_DEVICE memory is always set PG_reserved. We want to
> change that.
>
> Let's make sure that the logic in the function won't change. Once we no
> longer set these pages to reserved, we can rework this function to
> perform separate checks for ZONE_DEVICE (split from PG_reserved checks).
>
> Cc: Kees Cook <keescook@chromium.org>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Kate Stewart <kstewart@linuxfoundation.org>
> Cc: Allison Randal <allison@lohutok.net>
> Cc: "Isaac J. Manjarres" <isaacm@codeaurora.org>
> Cc: Qian Cai <cai@lca.pw>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
> mm/usercopy.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/mm/usercopy.c b/mm/usercopy.c
> index 660717a1ea5c..a3ac4be35cde 100644
> --- a/mm/usercopy.c
> +++ b/mm/usercopy.c
> @@ -203,14 +203,15 @@ static inline void check_page_span(const void *ptr, unsigned long n,
> * device memory), or CMA. Otherwise, reject since the object spans
> * several independently allocated pages.
> */
> - is_reserved = PageReserved(page);
> + is_reserved = PageReserved(page) || is_zone_device_page(page);
> is_cma = is_migrate_cma_page(page);
> if (!is_reserved && !is_cma)
> usercopy_abort("spans multiple pages", NULL, to_user, 0, n);
>
> for (ptr += PAGE_SIZE; ptr <= end; ptr += PAGE_SIZE) {
> page = virt_to_head_page(ptr);
> - if (is_reserved && !PageReserved(page))
> + if (is_reserved && !(PageReserved(page) ||
> + is_zone_device_page(page)))
> usercopy_abort("spans Reserved and non-Reserved pages",
> NULL, to_user, 0, n);
> if (is_cma && !is_migrate_cma_page(page))
>
@Kees, would it be okay to stop checking against ZONE_DEVICE pages here
or is there a good rationale behind this?
(I would turn this patch into a simple update of the comment if we agree
that we don't care)
--
Thanks,
David / dhildenb
next prev parent reply other threads:[~2019-10-23 8:20 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-22 17:12 [PATCH RFC v1 00/12] mm: Don't mark hotplugged pages PG_reserved (including ZONE_DEVICE) David Hildenbrand
2019-10-22 17:12 ` [PATCH RFC v1 01/12] mm/memory_hotplug: Don't allow to online/offline memory blocks with holes David Hildenbrand
2019-10-24 3:53 ` Anshuman Khandual
2019-10-24 7:55 ` David Hildenbrand
2019-10-22 17:12 ` [PATCH RFC v1 02/12] mm/usercopy.c: Prepare check_page_span() for PG_reserved changes David Hildenbrand
2019-10-23 8:20 ` David Hildenbrand [this message]
2019-10-23 16:25 ` Kees Cook
2019-10-23 16:32 ` David Hildenbrand
2019-10-22 17:12 ` [PATCH RFC v1 03/12] KVM: x86/mmu: Prepare kvm_is_mmio_pfn() " David Hildenbrand
2019-10-22 17:12 ` [PATCH RFC v1 04/12] KVM: Prepare kvm_is_reserved_pfn() " David Hildenbrand
2019-10-22 17:12 ` [PATCH RFC v1 05/12] vfio/type1: Prepare is_invalid_reserved_pfn() " David Hildenbrand
2019-10-22 17:12 ` [PATCH RFC v1 06/12] staging/gasket: Prepare gasket_release_page() " David Hildenbrand
2019-10-23 8:17 ` David Hildenbrand
2019-10-22 17:12 ` [PATCH RFC v1 07/12] staging: kpc2000: Prepare transfer_complete_cb() " David Hildenbrand
2019-10-22 17:55 ` Matt Sickler
2019-10-22 21:01 ` David Hildenbrand
2019-10-22 17:12 ` [PATCH RFC v1 08/12] powerpc/book3s: Prepare kvmppc_book3s_instantiate_page() " David Hildenbrand
2019-10-22 17:12 ` [PATCH RFC v1 09/12] powerpc/64s: Prepare hash_page_do_lazy_icache() " David Hildenbrand
2019-10-22 17:12 ` [PATCH RFC v1 10/12] powerpc/mm: Prepare maybe_pte_to_page() " David Hildenbrand
2019-10-22 17:12 ` [PATCH RFC v1 11/12] x86/mm: Prepare __ioremap_check_ram() " David Hildenbrand
2019-10-22 17:12 ` [PATCH RFC v1 12/12] mm/memory_hotplug: Don't mark pages PG_reserved when initializing the memmap David Hildenbrand
2019-10-22 21:54 ` [PATCH RFC v1 00/12] mm: Don't mark hotplugged pages PG_reserved (including ZONE_DEVICE) Dan Williams
2019-10-23 7:26 ` David Hildenbrand
2019-10-23 17:09 ` Dan Williams
2019-10-23 17:27 ` David Hildenbrand
2019-10-23 19:39 ` Dan Williams
2019-10-23 21:22 ` David Hildenbrand
2019-10-24 12:50 ` David Hildenbrand
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=a8313fb1-50f3-9083-fd07-297ddf86658e@redhat.com \
--to=david@redhat.com \
--cc=Matt.Sickler@daktronics.com \
--cc=akpm@linux-foundation.org \
--cc=alex.williamson@redhat.com \
--cc=alexander.duyck@gmail.com \
--cc=alexander.h.duyck@linux.intel.com \
--cc=allison@lohutok.net \
--cc=aneesh.kumar@linux.ibm.com \
--cc=anshuman.khandual@arm.com \
--cc=anthony.yznaga@oracle.com \
--cc=benchan@chromium.org \
--cc=benh@kernel.crashing.org \
--cc=bnvandana@gmail.com \
--cc=boris.ostrovsky@oracle.com \
--cc=bp@alien8.de \
--cc=cai@lca.pw \
--cc=christophe.leroy@c-s.fr \
--cc=cohuck@redhat.com \
--cc=dan.carpenter@oracle.com \
--cc=dan.j.williams@intel.com \
--cc=dave.hansen@linux.intel.com \
--cc=devel@driverdev.osuosl.org \
--cc=festevam@gmail.com \
--cc=gregkh@linuxfoundation.org \
--cc=haiyangz@microsoft.com \
--cc=hannes@cmpxchg.org \
--cc=hpa@zytor.com \
--cc=isaacm@codeaurora.org \
--cc=jeremy@azazel.net \
--cc=jgross@suse.com \
--cc=jmattson@google.com \
--cc=joro@8bytes.org \
--cc=karahmed@amazon.de \
--cc=keescook@chromium.org \
--cc=kstewart@linuxfoundation.org \
--cc=kvm-ppc@vger.kernel.org \
--cc=kvm@vger.kernel.org \
--cc=kys@microsoft.com \
--cc=linux-hyperv@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=luto@kernel.org \
--cc=madhumithabiw@gmail.com \
--cc=mgorman@techsingularity.net \
--cc=mhocko@kernel.org \
--cc=mhocko@suse.com \
--cc=mingo@redhat.com \
--cc=mpe@ellerman.id.au \
--cc=nishkadg.linux@gmail.com \
--cc=npiggin@gmail.com \
--cc=osalvador@suse.de \
--cc=pasha.tatashin@soleen.com \
--cc=paulus@ozlabs.org \
--cc=paulus@samba.org \
--cc=pavel.tatashin@microsoft.com \
--cc=pbonzini@redhat.com \
--cc=peterz@infradead.org \
--cc=rkrcmar@redhat.com \
--cc=rppt@linux.ibm.com \
--cc=rppt@linux.vnet.ibm.com \
--cc=rspringer@google.com \
--cc=sashal@kernel.org \
--cc=sean.j.christopherson@intel.com \
--cc=simon@nikanor.nu \
--cc=sstabellini@kernel.org \
--cc=sthemmin@microsoft.com \
--cc=tglx@linutronix.de \
--cc=toddpoynor@google.com \
--cc=vbabka@suse.cz \
--cc=vkuznets@redhat.com \
--cc=wanpengli@tencent.com \
--cc=x86@kernel.org \
--cc=xen-devel@lists.xenproject.org \
--cc=yuehaibing@huawei.com \
/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).