Re: [PATCH V2 4/8] mm/highmem: Add VM_BUG_ON() to mem*_page() calls

2021-02-11 Thread David Sterba
On Wed, Feb 10, 2021 at 01:22:28PM -0800, Ira Weiny wrote: > On Wed, Feb 10, 2021 at 06:56:06PM +, Matthew Wilcox wrote: > > On Wed, Feb 10, 2021 at 08:29:01AM -0800, Ira Weiny wrote: > > > And I thought it was a good idea. Any file system development should have > > > tests with DEBUG_VM

Re: [PATCH V2 4/8] mm/highmem: Add VM_BUG_ON() to mem*_page() calls

2021-02-10 Thread Ira Weiny
On Wed, Feb 10, 2021 at 06:56:06PM +, Matthew Wilcox wrote: > On Wed, Feb 10, 2021 at 08:29:01AM -0800, Ira Weiny wrote: > > And I thought it was a good idea. Any file system development should have > > tests with DEBUG_VM which should cover Matthew's concern while not having > > the > >

Re: [PATCH V2 4/8] mm/highmem: Add VM_BUG_ON() to mem*_page() calls

2021-02-10 Thread Matthew Wilcox
On Wed, Feb 10, 2021 at 08:29:01AM -0800, Ira Weiny wrote: > And I thought it was a good idea. Any file system development should have > tests with DEBUG_VM which should cover Matthew's concern while not having the > overhead in production. Seemed like a decent compromise? Why do you think

Re: [PATCH V2 4/8] mm/highmem: Add VM_BUG_ON() to mem*_page() calls

2021-02-10 Thread Ira Weiny
On Wed, Feb 10, 2021 at 04:41:34PM +, Christoph Hellwig wrote: > On Wed, Feb 10, 2021 at 08:29:01AM -0800, Ira Weiny wrote: > > On Wed, Feb 10, 2021 at 12:55:02PM +, Christoph Hellwig wrote: > > > On Tue, Feb 09, 2021 at 10:22:17PM -0800, ira.we...@intel.com wrote: > > > > From: Ira Weiny

Re: [PATCH V2 4/8] mm/highmem: Add VM_BUG_ON() to mem*_page() calls

2021-02-10 Thread Christoph Hellwig
On Wed, Feb 10, 2021 at 08:29:01AM -0800, Ira Weiny wrote: > On Wed, Feb 10, 2021 at 12:55:02PM +, Christoph Hellwig wrote: > > On Tue, Feb 09, 2021 at 10:22:17PM -0800, ira.we...@intel.com wrote: > > > From: Ira Weiny > > > > > > Add VM_BUG_ON bounds checks to ensure the newly lifted and

Re: [PATCH V2 4/8] mm/highmem: Add VM_BUG_ON() to mem*_page() calls

2021-02-10 Thread Ira Weiny
On Wed, Feb 10, 2021 at 06:57:30AM +, Chaitanya Kulkarni wrote: > On 2/9/21 22:25, ira.we...@intel.com wrote: > > From: Ira Weiny > > > > Add VM_BUG_ON bounds checks to ensure the newly lifted and created page > > memory operations do not result in corrupted data in neighbor pages and > > to

Re: [PATCH V2 4/8] mm/highmem: Add VM_BUG_ON() to mem*_page() calls

2021-02-10 Thread Ira Weiny
On Wed, Feb 10, 2021 at 12:55:02PM +, Christoph Hellwig wrote: > On Tue, Feb 09, 2021 at 10:22:17PM -0800, ira.we...@intel.com wrote: > > From: Ira Weiny > > > > Add VM_BUG_ON bounds checks to ensure the newly lifted and created page > > memory operations do not result in corrupted data in

Re: [PATCH V2 4/8] mm/highmem: Add VM_BUG_ON() to mem*_page() calls

2021-02-10 Thread Christoph Hellwig
On Tue, Feb 09, 2021 at 10:22:17PM -0800, ira.we...@intel.com wrote: > From: Ira Weiny > > Add VM_BUG_ON bounds checks to ensure the newly lifted and created page > memory operations do not result in corrupted data in neighbor pages and > to make them consistent with zero_user().[1][2]

Re: [PATCH V2 4/8] mm/highmem: Add VM_BUG_ON() to mem*_page() calls

2021-02-09 Thread Chaitanya Kulkarni
On 2/9/21 22:25, ira.we...@intel.com wrote: > From: Ira Weiny > > Add VM_BUG_ON bounds checks to ensure the newly lifted and created page > memory operations do not result in corrupted data in neighbor pages and > to make them consistent with zero_user().[1][2] > I did not understand this, in my

[PATCH V2 4/8] mm/highmem: Add VM_BUG_ON() to mem*_page() calls

2021-02-09 Thread ira . weiny
From: Ira Weiny Add VM_BUG_ON bounds checks to ensure the newly lifted and created page memory operations do not result in corrupted data in neighbor pages and to make them consistent with zero_user().[1][2] [1] https://lore.kernel.org/lkml/20201210053502.gs1563...@iweiny-desk2.sc.intel.com/