6.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Guangguan Wang <guangguan.wang@xxxxxxxxxxxxxxxxx> [ Upstream commit 3ac14b9dfbd345e891d48d89f6c2fa519848f0f4 ] SG_MAX_SINGLE_ALLOC is used to limit maximum number of entries that will be allocated in one piece of scatterlist. When the entries of scatterlist exceeds SG_MAX_SINGLE_ALLOC, sg chain will be used. From commit 7c703e54cc71 ("arch: switch the default on ARCH_HAS_SG_CHAIN"), we can know that the macro CONFIG_ARCH_NO_SG_CHAIN is used to identify whether sg chain is supported. So, SMC-R's rmb buffer should be limited by SG_MAX_SINGLE_ALLOC only when the macro CONFIG_ARCH_NO_SG_CHAIN is defined. Fixes: a3fe3d01bd0d ("net/smc: introduce sg-logic for RMBs") Signed-off-by: Guangguan Wang <guangguan.wang@xxxxxxxxxxxxxxxxx> Co-developed-by: Wen Gu <guwen@xxxxxxxxxxxxxxxxx> Signed-off-by: Wen Gu <guwen@xxxxxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/smc/smc_core.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index fafdb97adfad9..acca3b1a068f0 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -2015,7 +2015,6 @@ int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini) */ static u8 smc_compress_bufsize(int size, bool is_smcd, bool is_rmb) { - const unsigned int max_scat = SG_MAX_SINGLE_ALLOC * PAGE_SIZE; u8 compressed; if (size <= SMC_BUF_MIN_SIZE) @@ -2025,9 +2024,11 @@ static u8 smc_compress_bufsize(int size, bool is_smcd, bool is_rmb) compressed = min_t(u8, ilog2(size) + 1, is_smcd ? SMCD_DMBE_SIZES : SMCR_RMBE_SIZES); +#ifdef CONFIG_ARCH_NO_SG_CHAIN if (!is_smcd && is_rmb) /* RMBs are backed by & limited to max size of scatterlists */ - compressed = min_t(u8, compressed, ilog2(max_scat >> 14)); + compressed = min_t(u8, compressed, ilog2((SG_MAX_SINGLE_ALLOC * PAGE_SIZE) >> 14)); +#endif return compressed; } -- 2.43.0