The patch titled
Subject: include/linux/gfp.h: further document GFP_DMA32
has been added to the -mm tree. Its filename is
gfp-further-document-gfp_dma32.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/gfp-further-document-gfp_dma32.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/gfp-further-document-gfp_dma32.patch
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------------------------------------------------------
From: Miles Chen <miles.chen@xxxxxxxxxxxx>
Subject: include/linux/gfp.h: further document GFP_DMA32
kmalloc(..., GFP_DMA32) does not return DMA32 memory because the DMA32
kmalloc cache array is not implemented. (Reason: there is no such user in
kernel).
Put a short comment about this so people can understand this by reading
the comment.
[1] https://lists.linuxfoundation.org/pipermail/iommu/2018-December/031696.html
Link: https://lkml.kernel.org/r/20211207093610.6406-1-miles.chen@xxxxxxxxxxxx
Signed-off-by: Miles Chen <miles.chen@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/gfp.h | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/include/linux/gfp.h~gfp-further-document-gfp_dma32
+++ a/include/linux/gfp.h
@@ -298,7 +298,9 @@ struct vm_area_struct;
* lowest zone as a type of emergency reserve.
*
* %GFP_DMA32 is similar to %GFP_DMA except that the caller requires a 32-bit
- * address.
+ * address. Note that kmalloc(..., GFP_DMA32) does not return DMA32 memory
+ * because the DMA32 kmalloc cache array is not implemented.
+ * (Reason: there is no such user in kernel).
*
* %GFP_HIGHUSER is for userspace allocations that may be mapped to userspace,
* do not need to be directly accessible by the kernel but that cannot
_
Patches currently in -mm which might be from miles.chen@xxxxxxxxxxxx are
gfp-further-document-gfp_dma32.patch
