xfs
[Top] [All Lists]

Re: %u-order allocation failed

Subject: Re: %u-order allocation failed
From: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Date: Sat, 6 Oct 2001 22:13:03 +0200
Sender: owner-linux-xfs@xxxxxxxxxxx
>
>OK, but my patch uses vmalloc only as a fallback when buddy fails. The
>probability that buddy fails is small. It is slower but with very small
>probability.
>
>It is perfectly OK to have a bit slower access to task_struct with
>probability 1/1000000.
>
>But it is ***BAD*BUG*** if allocation of task_struct fails with
>probability 1/1000000.

I missed the beginning of the thread, sorry if that question was
already answered,

What about all the code that still consider kmalloc'ed memory is
safe for use with virt_to_bus and friends and is contiguous
physically for DMA ? In some cases (non-PCI devices, embedded
platforms, etc...), the pci_consistent API is not an option.
That means that __GFP_VMALLOC can't be part of GFP_KERNEL or
many driver will break in horrible ways (random memory corruption).

Ben.



<Prev in Thread] Current Thread [Next in Thread>