| From | Greg Kroah-Hartman <> | Subject | [PATCH 5.19 061/207] net: mana: Add rmb after checking owner bits | Date | Mon, 26 Sep 2022 12:10:50 +0200 |
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From: Haiyang Zhang <haiyangz@microsoft.com>
commit 6fd2c68da55c552f86e401ebe40c4a619025ef69 upstream.
Per GDMA spec, rmb is necessary after checking owner_bits, before reading EQ or CQ entries.
Add rmb in these two places to comply with the specs.
Cc: stable@vger.kernel.org Fixes: ca9c54d2d6a5 ("net: mana: Add a driver for Microsoft Azure Network Adapter (MANA)") Reported-by: Sinan Kaya <Sinan.Kaya@microsoft.com> Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> Reviewed-by: Dexuan Cui <decui@microsoft.com> Link: https://lore.kernel.org/r/1662928805-15861-1-git-send-email-haiyangz@microsoft.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- drivers/net/ethernet/microsoft/mana/gdma_main.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
--- a/drivers/net/ethernet/microsoft/mana/gdma_main.c +++ b/drivers/net/ethernet/microsoft/mana/gdma_main.c @@ -370,6 +370,11 @@ static void mana_gd_process_eq_events(vo break; } + /* Per GDMA spec, rmb is necessary after checking owner_bits, before + * reading eqe. + */ + rmb(); + mana_gd_process_eqe(eq); eq->head++; @@ -1107,6 +1112,11 @@ static int mana_gd_read_cqe(struct gdma_ if (WARN_ON_ONCE(owner_bits != new_bits)) return -1; + /* Per GDMA spec, rmb is necessary after checking owner_bits, before + * reading completion info + */ + rmb(); + comp->wq_num = cqe->cqe_info.wq_num; comp->is_sq = cqe->cqe_info.is_sq; memcpy(comp->cqe_data, cqe->cqe_data, GDMA_COMP_DATA_SIZE);
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