From: Pankaj Gupta <pagupta@redhat.com>
To: Dan Williams <dan.j.williams@intel.com>
Cc: akpm@linux-foundation.org, stable@vger.kernel.org,
Piotr Balcer <piotr.balcer@intel.com>, Yan Ma <yan.ma@intel.com>,
"Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>,
Chandan Rajendra <chandan@linux.ibm.com>, Jan Kara <jack@suse.cz>,
Matthew Wilcox <willy@infradead.org>,
Souptick Joarder <jrdr.linux@gmail.com>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] mm/huge_memory: Fix vmf_insert_pfn_{pmd, pud}() crash, handle unaligned addresses
Date: Fri, 10 May 2019 01:42:17 -0400 (EDT) [thread overview]
Message-ID: <1750394500.27863545.1557466937334.JavaMail.zimbra@redhat.com> (raw)
In-Reply-To: <155741946350.372037.11148198430068238140.stgit@dwillia2-desk3.amr.corp.intel.com>
>
> Starting with commit c6f3c5ee40c1 "mm/huge_memory.c: fix modifying of
> page protection by insert_pfn_pmd()" vmf_insert_pfn_pmd() internally
> calls pmdp_set_access_flags(). That helper enforces a pmd aligned
> @address argument via VM_BUG_ON() assertion.
>
> Update the implementation to take a 'struct vm_fault' argument directly
> and apply the address alignment fixup internally to fix crash signatures
> like:
>
> kernel BUG at arch/x86/mm/pgtable.c:515!
> invalid opcode: 0000 [#1] SMP NOPTI
> CPU: 51 PID: 43713 Comm: java Tainted: G OE 4.19.35 #1
> [..]
> RIP: 0010:pmdp_set_access_flags+0x48/0x50
> [..]
> Call Trace:
> vmf_insert_pfn_pmd+0x198/0x350
> dax_iomap_fault+0xe82/0x1190
> ext4_dax_huge_fault+0x103/0x1f0
> ? __switch_to_asm+0x40/0x70
> __handle_mm_fault+0x3f6/0x1370
> ? __switch_to_asm+0x34/0x70
> ? __switch_to_asm+0x40/0x70
> handle_mm_fault+0xda/0x200
> __do_page_fault+0x249/0x4f0
> do_page_fault+0x32/0x110
> ? page_fault+0x8/0x30
> page_fault+0x1e/0x30
>
> Cc: vger.kernel.org>
> Fixes: c6f3c5ee40c1 ("mm/huge_memory.c: fix modifying of page protection by
> insert_pfn_pmd()")
> Reported-by: Piotr Balcer <piotr.balcer@intel.com>
> Tested-by: Yan Ma <yan.ma@intel.com>
> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
> Cc: Chandan Rajendra <chandan@linux.ibm.com>
> Cc: Jan Kara suse.cz>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Matthew Wilcox infradead.org>
> Cc: Souptick Joarder <jrdr.linux@gmail.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> ---
>
> drivers/dax/device.c | 6 ++----
> fs/dax.c | 6 ++----
> include/linux/huge_mm.h | 6 ++----
> mm/huge_memory.c | 16 ++++++++++------
> 4 files changed, 16 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/dax/device.c b/drivers/dax/device.c
> index e428468ab661..996d68ff992a 100644
> --- a/drivers/dax/device.c
> +++ b/drivers/dax/device.c
> @@ -184,8 +184,7 @@ static vm_fault_t __dev_dax_pmd_fault(struct dev_dax
> *dev_dax,
>
> *pfn = phys_to_pfn_t(phys, dax_region->pfn_flags);
>
> - return vmf_insert_pfn_pmd(vmf->vma, vmf->address, vmf->pmd, *pfn,
> - vmf->flags & FAULT_FLAG_WRITE);
> + return vmf_insert_pfn_pmd(vmf, *pfn, vmf->flags & FAULT_FLAG_WRITE);
> }
>
> #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
> @@ -235,8 +234,7 @@ static vm_fault_t __dev_dax_pud_fault(struct dev_dax
> *dev_dax,
>
> *pfn = phys_to_pfn_t(phys, dax_region->pfn_flags);
>
> - return vmf_insert_pfn_pud(vmf->vma, vmf->address, vmf->pud, *pfn,
> - vmf->flags & FAULT_FLAG_WRITE);
> + return vmf_insert_pfn_pud(vmf, *pfn, vmf->flags & FAULT_FLAG_WRITE);
> }
> #else
> static vm_fault_t __dev_dax_pud_fault(struct dev_dax *dev_dax,
> diff --git a/fs/dax.c b/fs/dax.c
> index e5e54da1715f..83009875308c 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -1575,8 +1575,7 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault
> *vmf, pfn_t *pfnp,
> }
>
> trace_dax_pmd_insert_mapping(inode, vmf, PMD_SIZE, pfn, entry);
> - result = vmf_insert_pfn_pmd(vma, vmf->address, vmf->pmd, pfn,
> - write);
> + result = vmf_insert_pfn_pmd(vmf, pfn, write);
> break;
> case IOMAP_UNWRITTEN:
> case IOMAP_HOLE:
> @@ -1686,8 +1685,7 @@ dax_insert_pfn_mkwrite(struct vm_fault *vmf, pfn_t pfn,
> unsigned int order)
> ret = vmf_insert_mixed_mkwrite(vmf->vma, vmf->address, pfn);
> #ifdef CONFIG_FS_DAX_PMD
> else if (order == PMD_ORDER)
> - ret = vmf_insert_pfn_pmd(vmf->vma, vmf->address, vmf->pmd,
> - pfn, true);
> + ret = vmf_insert_pfn_pmd(vmf, pfn, FAULT_FLAG_WRITE);
> #endif
> else
> ret = VM_FAULT_FALLBACK;
> diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
> index 381e872bfde0..7cd5c150c21d 100644
> --- a/include/linux/huge_mm.h
> +++ b/include/linux/huge_mm.h
> @@ -47,10 +47,8 @@ extern bool move_huge_pmd(struct vm_area_struct *vma,
> unsigned long old_addr,
> extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
> unsigned long addr, pgprot_t newprot,
> int prot_numa);
> -vm_fault_t vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long
> addr,
> - pmd_t *pmd, pfn_t pfn, bool write);
> -vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long
> addr,
> - pud_t *pud, pfn_t pfn, bool write);
> +vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write);
> +vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write);
> enum transparent_hugepage_flag {
> TRANSPARENT_HUGEPAGE_FLAG,
> TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index 165ea46bf149..4310c6e9e5a3 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -793,11 +793,13 @@ static void insert_pfn_pmd(struct vm_area_struct *vma,
> unsigned long addr,
> pte_free(mm, pgtable);
> }
>
> -vm_fault_t vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long
> addr,
> - pmd_t *pmd, pfn_t pfn, bool write)
> +vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write)
> {
> + unsigned long addr = vmf->address & PMD_MASK;
> + struct vm_area_struct *vma = vmf->vma;
> pgprot_t pgprot = vma->vm_page_prot;
> pgtable_t pgtable = NULL;
> +
> /*
> * If we had pmd_special, we could avoid all these restrictions,
> * but we need to be consistent with PTEs and architectures that
> @@ -820,7 +822,7 @@ vm_fault_t vmf_insert_pfn_pmd(struct vm_area_struct *vma,
> unsigned long addr,
>
> track_pfn_insert(vma, &pgprot, pfn);
>
> - insert_pfn_pmd(vma, addr, pmd, pfn, pgprot, write, pgtable);
> + insert_pfn_pmd(vma, addr, vmf->pmd, pfn, pgprot, write, pgtable);
> return VM_FAULT_NOPAGE;
> }
> EXPORT_SYMBOL_GPL(vmf_insert_pfn_pmd);
> @@ -869,10 +871,12 @@ static void insert_pfn_pud(struct vm_area_struct *vma,
> unsigned long addr,
> spin_unlock(ptl);
> }
>
> -vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long
> addr,
> - pud_t *pud, pfn_t pfn, bool write)
> +vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write)
> {
> + unsigned long addr = vmf->address & PUD_MASK;
> + struct vm_area_struct *vma = vmf->vma;
> pgprot_t pgprot = vma->vm_page_prot;
> +
> /*
> * If we had pud_special, we could avoid all these restrictions,
> * but we need to be consistent with PTEs and architectures that
> @@ -889,7 +893,7 @@ vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma,
> unsigned long addr,
>
> track_pfn_insert(vma, &pgprot, pfn);
>
> - insert_pfn_pud(vma, addr, pud, pfn, pgprot, write);
> + insert_pfn_pud(vma, addr, vmf->pud, pfn, pgprot, write);
> return VM_FAULT_NOPAGE;
> }
> EXPORT_SYMBOL_GPL(vmf_insert_pfn_pud);
>
Thanks for the patch.
This patch solves the issue faced while testing virtio pmem.
Tested-by: Pankaj Gupta <pagupta@redhat.com>
>
next prev parent reply other threads:[~2019-05-10 5:42 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-09 16:31 [PATCH] mm/huge_memory: Fix vmf_insert_pfn_{pmd, pud}() crash, handle unaligned addresses Dan Williams
2019-05-09 17:42 ` Matthew Wilcox
2019-05-09 19:32 ` Jan Kara
2019-05-10 5:42 ` Pankaj Gupta [this message]
2019-05-10 21:02 ` Aneesh Kumar K.V
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=1750394500.27863545.1557466937334.JavaMail.zimbra@redhat.com \
--to=pagupta@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=aneesh.kumar@linux.ibm.com \
--cc=chandan@linux.ibm.com \
--cc=dan.j.williams@intel.com \
--cc=jack@suse.cz \
--cc=jrdr.linux@gmail.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=piotr.balcer@intel.com \
--cc=stable@vger.kernel.org \
--cc=willy@infradead.org \
--cc=yan.ma@intel.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).