On 6/4/19 6:06 PM, Ming Lei wrote:
If user doesn't ask to pre-allocate by passing zero 'nents_first_chunk' to sg_alloc_table_chained, we need to make sure that 'first_chunk' is cleared. Otherwise, __sg_alloc_table() still may think that the 1st SGL should be from the pre-allocation.Fixes the issue by clearing 'first_chunk' in sg_alloc_table_chained() if 'nents_first_chunk' is zero. Cc: Christoph Hellwig <h...@lst.de> Cc: Bart Van Assche <bvanass...@acm.org> Cc: Ewan D. Milne <emi...@redhat.com> Cc: Hannes Reinecke <h...@suse.com> Cc: Guenter Roeck <li...@roeck-us.net> Fixes: c3288dd8c232 ("scsi: core: avoid pre-allocating big SGL for data")
Shouldn't the "Fixes:" tag be left out from this patch? I don't think that this patch by itself fixes anything. Isn't this patch something that is necessary to make patch 2/3 in this series work? How about indicating that by mentioning it in the commit message?
Reported-by: Guenter Roeck <li...@roeck-us.net> Tested-by: Guenter Roeck <li...@roeck-us.net> Signed-off-by: Ming Lei <ming....@redhat.com> --- lib/sg_pool.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/sg_pool.c b/lib/sg_pool.c index 47eecbe094d8..e042a1722615 100644 --- a/lib/sg_pool.c +++ b/lib/sg_pool.c @@ -122,7 +122,7 @@ int sg_alloc_table_chained(struct sg_table *table, int nents, }/* User supposes that the 1st SGL includes real entry */- if (nents_first_chunk == 1) { + if (nents_first_chunk <= 1) { first_chunk = NULL; nents_first_chunk = 0; }
How about also updating the kernel-doc header above sg_alloc_table_chained() such that it is made clear that @first_chunk is ignored if nents_first_chunk <= 1 ? Otherwise this patch looks fine to me.
Bart.
