> -----Original Message----- > From: Radu Nicolau <[email protected]> > Sent: Friday 27 February 2026 14:00 > To: [email protected] > Cc: Marat Khalili <[email protected]>; Radu Nicolau > <[email protected]>; [email protected]; > [email protected]; Yipeng Wang <[email protected]>; Sameh > Gobriel > <[email protected]>; Bruce Richardson <[email protected]>; > Vladimir Medvedkin > <[email protected]>; Yerden Zhumabekov <[email protected]>; > Pablo de Lara > <[email protected]> > Subject: [PATCH v3] hash: fix pointer alignment > > rte_hash_crc assumes input pointer address is 8 byte aligned > which may not be always the case. > This fix aligns the input pointer before proceeding to process it > in 8 byte chunks. > > Bugzilla ID: 1892 > Fixes: 504a29af13a7 ("hash: fix strict-aliasing for CRC") > Cc: [email protected] > Cc: [email protected] > > Signed-off-by: Radu Nicolau <[email protected]> > Acked-by: Marat Khalili <[email protected]> > --- > v3: revert alignment code to simple loop, it was getting too complex for a > corner case > > > lib/hash/rte_hash_crc.h | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/lib/hash/rte_hash_crc.h b/lib/hash/rte_hash_crc.h > index fa07c97685..f60f4598d8 100644 > --- a/lib/hash/rte_hash_crc.h > +++ b/lib/hash/rte_hash_crc.h > @@ -127,6 +127,16 @@ rte_hash_crc(const void *data, uint32_t data_len, > uint32_t init_val) > unsigned i; > uintptr_t pd = (uintptr_t) data; > > + /* align input to 8 byte boundary if needed */ > + if (pd & 0x7) { > + unsigned int unaligned_bytes = RTE_MIN(8 - (pd & 0x7), > data_len); > + for (i = 0; i < unaligned_bytes; i++) { > + init_val = rte_hash_crc_1byte(*(const uint8_t *)pd, > init_val); > + pd++; > + data_len--; > + } > + } > + > for (i = 0; i < data_len / 8; i++) { > init_val = rte_hash_crc_8byte(*(const uint64_t *)pd, init_val); > pd += 8; > -- > 2.52.0 >
My custom checks now pass even for small inputs. (I also support the idea to simplify it to a single loop, until we have actual benchmarks showing that some alternative is better. Same for many possible ways to simplify if and/or for condition.) Acked-by: Marat Khalili <[email protected]> Tested-by: Marat Khalili <[email protected]>
