* [PATCH] mm: fix BUG_ON() in vmf_insert_pfn_pud() from VM_MIXEDMAP removal
@ 2018-08-30 20:06 Dave Jiang
2018-08-30 20:12 ` Jeff Moyer
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Dave Jiang @ 2018-08-30 20:06 UTC (permalink / raw)
To: akpm; +Cc: linux-mm, jack, linux-nvdimm
It looks like I missed the PUD path when doing VM_MIXEDMAP removal.
This can be triggered by:
1. Boot with memmap=4G!8G
2. build ndctl with destructive flag on
3. make TESTS=device-dax check
[ +0.000675] kernel BUG at mm/huge_memory.c:824!
Applying the same change that was applied to vmf_insert_pfn_pmd() in the
original patch.
Fixes: e1fb4a08649 ("dax: remove VM_MIXEDMAP for fsdax and device dax")
Reported-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
mm/huge_memory.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index c3bc7e9c9a2a..533f9b00147d 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -821,11 +821,11 @@ vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
* but we need to be consistent with PTEs and architectures that
* can't support a 'special' bit.
*/
- BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)));
+ BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) &&
+ !pfn_t_devmap(pfn));
BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) ==
(VM_PFNMAP|VM_MIXEDMAP));
BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(vma->vm_flags));
- BUG_ON(!pfn_t_devmap(pfn));
if (addr < vma->vm_start || addr >= vma->vm_end)
return VM_FAULT_SIGBUS;
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^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH] mm: fix BUG_ON() in vmf_insert_pfn_pud() from VM_MIXEDMAP removal
2018-08-30 20:06 [PATCH] mm: fix BUG_ON() in vmf_insert_pfn_pud() from VM_MIXEDMAP removal Dave Jiang
@ 2018-08-30 20:12 ` Jeff Moyer
2018-08-30 20:28 ` Verma, Vishal L
2018-08-31 10:22 ` Jan Kara
2 siblings, 0 replies; 6+ messages in thread
From: Jeff Moyer @ 2018-08-30 20:12 UTC (permalink / raw)
To: Dave Jiang; +Cc: linux-mm, akpm, linux-nvdimm, jack
Dave Jiang <dave.jiang@intel.com> writes:
> It looks like I missed the PUD path when doing VM_MIXEDMAP removal.
> This can be triggered by:
> 1. Boot with memmap=4G!8G
> 2. build ndctl with destructive flag on
> 3. make TESTS=device-dax check
>
> [ +0.000675] kernel BUG at mm/huge_memory.c:824!
>
> Applying the same change that was applied to vmf_insert_pfn_pmd() in the
> original patch.
>
> Fixes: e1fb4a08649 ("dax: remove VM_MIXEDMAP for fsdax and device dax")
>
> Reported-by: Vishal Verma <vishal.l.verma@intel.com>
> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
> ---
> mm/huge_memory.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index c3bc7e9c9a2a..533f9b00147d 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -821,11 +821,11 @@ vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
> * but we need to be consistent with PTEs and architectures that
> * can't support a 'special' bit.
> */
> - BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)));
> + BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) &&
> + !pfn_t_devmap(pfn));
> BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) ==
> (VM_PFNMAP|VM_MIXEDMAP));
> BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(vma->vm_flags));
> - BUG_ON(!pfn_t_devmap(pfn));
>
> if (addr < vma->vm_start || addr >= vma->vm_end)
> return VM_FAULT_SIGBUS;
>
> _______________________________________________
> Linux-nvdimm mailing list
> Linux-nvdimm@lists.01.org
> https://lists.01.org/mailman/listinfo/linux-nvdimm
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^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] mm: fix BUG_ON() in vmf_insert_pfn_pud() from VM_MIXEDMAP removal
2018-08-30 20:06 [PATCH] mm: fix BUG_ON() in vmf_insert_pfn_pud() from VM_MIXEDMAP removal Dave Jiang
2018-08-30 20:12 ` Jeff Moyer
@ 2018-08-30 20:28 ` Verma, Vishal L
2018-08-31 10:22 ` Jan Kara
2 siblings, 0 replies; 6+ messages in thread
From: Verma, Vishal L @ 2018-08-30 20:28 UTC (permalink / raw)
To: Jiang, Dave, akpm; +Cc: linux-mm, jack, linux-nvdimm
On Thu, 2018-08-30 at 13:06 -0700, Dave Jiang wrote:
> It looks like I missed the PUD path when doing VM_MIXEDMAP removal.
> This can be triggered by:
> 1. Boot with memmap=4G!8G
> 2. build ndctl with destructive flag on
> 3. make TESTS=device-dax check
>
> [ +0.000675] kernel BUG at mm/huge_memory.c:824!
>
> Applying the same change that was applied to vmf_insert_pfn_pmd() in
> the
> original patch.
>
> Fixes: e1fb4a08649 ("dax: remove VM_MIXEDMAP for fsdax and device
> dax")
>
> Reported-by: Vishal Verma <vishal.l.verma@intel.com>
> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> ---
> mm/huge_memory.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
This fixes the unit test failure, feel free to add:
Tested-by: Vishal Verma <vishal.l.verma@intel.com>
>
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index c3bc7e9c9a2a..533f9b00147d 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -821,11 +821,11 @@ vm_fault_t vmf_insert_pfn_pud(struct
> vm_area_struct *vma, unsigned long addr,
> * but we need to be consistent with PTEs and architectures
> that
> * can't support a 'special' bit.
> */
> - BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)));
> + BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) &&
> + !pfn_t_devmap(pfn));
> BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) ==
> (VM_PFNMAP|VM_MIXEDM
> AP));
> BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(vma-
> >vm_flags));
> - BUG_ON(!pfn_t_devmap(pfn));
>
> if (addr < vma->vm_start || addr >= vma->vm_end)
> return VM_FAULT_SIGBUS;
>
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^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] mm: fix BUG_ON() in vmf_insert_pfn_pud() from VM_MIXEDMAP removal
2018-08-30 20:06 [PATCH] mm: fix BUG_ON() in vmf_insert_pfn_pud() from VM_MIXEDMAP removal Dave Jiang
2018-08-30 20:12 ` Jeff Moyer
2018-08-30 20:28 ` Verma, Vishal L
@ 2018-08-31 10:22 ` Jan Kara
2 siblings, 0 replies; 6+ messages in thread
From: Jan Kara @ 2018-08-31 10:22 UTC (permalink / raw)
To: Dave Jiang; +Cc: linux-nvdimm, linux-mm, jack, akpm
On Thu 30-08-18 13:06:13, Dave Jiang wrote:
> It looks like I missed the PUD path when doing VM_MIXEDMAP removal.
> This can be triggered by:
> 1. Boot with memmap=4G!8G
> 2. build ndctl with destructive flag on
> 3. make TESTS=device-dax check
>
> [ +0.000675] kernel BUG at mm/huge_memory.c:824!
>
> Applying the same change that was applied to vmf_insert_pfn_pmd() in the
> original patch.
>
> Fixes: e1fb4a08649 ("dax: remove VM_MIXEDMAP for fsdax and device dax")
>
> Reported-by: Vishal Verma <vishal.l.verma@intel.com>
> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Looks good. You can add:
Reviewed-by: Jan Kara <jack@suse.cz>
Honza
> ---
> mm/huge_memory.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index c3bc7e9c9a2a..533f9b00147d 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -821,11 +821,11 @@ vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
> * but we need to be consistent with PTEs and architectures that
> * can't support a 'special' bit.
> */
> - BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)));
> + BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) &&
> + !pfn_t_devmap(pfn));
> BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) ==
> (VM_PFNMAP|VM_MIXEDMAP));
> BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(vma->vm_flags));
> - BUG_ON(!pfn_t_devmap(pfn));
>
> if (addr < vma->vm_start || addr >= vma->vm_end)
> return VM_FAULT_SIGBUS;
>
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR
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^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH] mm: fix BUG_ON() in vmf_insert_pfn_pud() from VM_MIXEDMAP removal
@ 2018-08-30 20:05 Dave Jiang
2018-08-30 20:15 ` Dave Jiang
0 siblings, 1 reply; 6+ messages in thread
From: Dave Jiang @ 2018-08-30 20:05 UTC (permalink / raw)
To: akpm; +Cc: jack, linux-mm, dan.j.williams, , linux-nvdimm
It looks like I missed the PUD path when doing VM_MIXEDMAP removal.
This can be triggered by:
1. Boot with memmap=4G!8G
2. build ndctl with destructive flag on
3. make TESTS=device-dax check
[ +0.000675] kernel BUG at mm/huge_memory.c:824!
Applying the same change that was applied to vmf_insert_pfn_pmd() in the
original patch.
Fixes: e1fb4a08649 ("dax: remove VM_MIXEDMAP for fsdax and device dax")
Reported-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
mm/huge_memory.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index c3bc7e9c9a2a..533f9b00147d 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -821,11 +821,11 @@ vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
* but we need to be consistent with PTEs and architectures that
* can't support a 'special' bit.
*/
- BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)));
+ BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) &&
+ !pfn_t_devmap(pfn));
BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) ==
(VM_PFNMAP|VM_MIXEDMAP));
BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(vma->vm_flags));
- BUG_ON(!pfn_t_devmap(pfn));
if (addr < vma->vm_start || addr >= vma->vm_end)
return VM_FAULT_SIGBUS;
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Linux-nvdimm@lists.01.org
https://lists.01.org/mailman/listinfo/linux-nvdimm
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH] mm: fix BUG_ON() in vmf_insert_pfn_pud() from VM_MIXEDMAP removal
2018-08-30 20:05 Dave Jiang
@ 2018-08-30 20:15 ` Dave Jiang
0 siblings, 0 replies; 6+ messages in thread
From: Dave Jiang @ 2018-08-30 20:15 UTC (permalink / raw)
To: akpm; +Cc: linux-mm, linux-nvdimm, jack
Please ignore this email. It had malformed mail header. I have resent a
non-broken one, which looks like has been ack'ed by Jeff.
On 08/30/2018 01:05 PM, Dave Jiang wrote:
> It looks like I missed the PUD path when doing VM_MIXEDMAP removal.
> This can be triggered by:
> 1. Boot with memmap=4G!8G
> 2. build ndctl with destructive flag on
> 3. make TESTS=device-dax check
>
> [ +0.000675] kernel BUG at mm/huge_memory.c:824!
>
> Applying the same change that was applied to vmf_insert_pfn_pmd() in the
> original patch.
>
> Fixes: e1fb4a08649 ("dax: remove VM_MIXEDMAP for fsdax and device dax")
>
> Reported-by: Vishal Verma <vishal.l.verma@intel.com>
> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> ---
> mm/huge_memory.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index c3bc7e9c9a2a..533f9b00147d 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -821,11 +821,11 @@ vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
> * but we need to be consistent with PTEs and architectures that
> * can't support a 'special' bit.
> */
> - BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)));
> + BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) &&
> + !pfn_t_devmap(pfn));
> BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) ==
> (VM_PFNMAP|VM_MIXEDMAP));
> BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(vma->vm_flags));
> - BUG_ON(!pfn_t_devmap(pfn));
>
> if (addr < vma->vm_start || addr >= vma->vm_end)
> return VM_FAULT_SIGBUS;
>
> _______________________________________________
> Linux-nvdimm mailing list
> Linux-nvdimm@lists.01.org
> https://lists.01.org/mailman/listinfo/linux-nvdimm
>
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^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2018-08-31 10:22 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2018-08-30 20:06 [PATCH] mm: fix BUG_ON() in vmf_insert_pfn_pud() from VM_MIXEDMAP removal Dave Jiang
2018-08-30 20:12 ` Jeff Moyer
2018-08-30 20:28 ` Verma, Vishal L
2018-08-31 10:22 ` Jan Kara
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2018-08-30 20:05 Dave Jiang
2018-08-30 20:15 ` Dave Jiang
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