On Aug 7, 2013, at 5:26 PM, Andrew Morton wrote: > On Wed, 7 Aug 2013 17:21:32 -0400 Ed Cashin <ecas...@coraid.com> wrote: ... >> Sorry. I tried to cover that but maybe should have separated it more >> clearly from the running text. >> >> The patch changes the current behavior encountered with direct I/O and aoe: >> >> aoe can BUG when direct I/O used >> >> ... to a new behavior: >> >> aoe does not BUG when direct I/O is used >> >> And the user will never know that instead aoe is manipulating the _count of >> the head page, even though that's what's happening with this patch applied. >> >> (The user-visible effects that motivated the older patch that added the BUG >> to aoe when page tails are used for block I/O was a VM_BUG_ON that occurred >> when the aoe driver manipulated the _count of a compound page tail.) > > OK, I added "Fix a BUG which can trigger when direct-IO is used with > AOE". Which kernel versions are affected?
That BUG was added to the aoe driver in a commit that first appears in v3.7. It persists until this patch adds the code that handles the situation that the BUG was intended to detect. [ecashin@marino linux]$ git describe --contains --match 'v*' 69cf2d85de773d998798e47e3335b85e5645d157 v3.7-rc1~110^2~22 [ecashin@marino linux]$ -- Ed Cashin ecas...@coraid.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
