Re: can a kmalloc be both GFP_ATOMIC and GFP_KERNEL at the same time?

On Mon, 30 Apr 2007, Andrew Morton wrote:

On Sat, 28 Apr 2007 09:40:39 -0400 (EDT) "Robert P. J. Day" <rpjday@xxxxxxxxxxxxxx> wrote:


i'd always assumed that the type flags of GFP_ATOMIC and GFP_KERNEL
were mutually exclusive when it came to calling kmalloc(), at least
based on everything i'd read. so i'm not sure how to interpret the
following:

drivers/scsi/aic7xxx_old.c: aic_dev = kmalloc(sizeof(struct aic_dev_data), GFP_ATOMIC | GFP_KERNEL);
drivers/message/i2o/device.c: resblk = kmalloc(buflen + 8, GFP_KERNEL | GFP_ATOMIC);

clarification?

GFP_ATOMIC implies that the memory comes from the zones which
GFP_KERNEL also uses. So the above usage of GFP_KERNEL is redundant
and should be removed.

hang on ... based on an email i just got, is that reference to
GFP_KERNEL "redundant" or "conflicting"? big difference there. and
is the proper fix to remove "GFP_KERNEL" in both cases?

rday
--
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Robert P. J. Day
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Waterloo, Ontario, CANADA

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