XXX commit 998c0bd2b3715244da7639cc4e6a2062cb79c3f4 upstream.
We have seen cases where an endpoint RX completion interrupt arrives while replenishing for the endpoint is underway. This causes another instance of replenishing to begin as part of completing the receive transaction. If this occurs it can lead to transaction corruption.
Use a new flag to ensure only one replenish instance for an endpoint executes at a time.
References: https://lore.kernel.org/stable/1643031462146216@kroah.com Fixes: 84f9bd12d46db ("soc: qcom: ipa: IPA endpoints") Signed-off-by: Alex Elder elder@linaro.org Signed-off-by: David S. Miller davem@davemloft.net --- drivers/net/ipa/ipa_endpoint.c | 12 ++++++++++++ drivers/net/ipa/ipa_endpoint.h | 2 ++ 2 files changed, 14 insertions(+)
diff --git a/drivers/net/ipa/ipa_endpoint.c b/drivers/net/ipa/ipa_endpoint.c index 80380f5966142..2e1e558275b1c 100644 --- a/drivers/net/ipa/ipa_endpoint.c +++ b/drivers/net/ipa/ipa_endpoint.c @@ -907,16 +907,27 @@ static void ipa_endpoint_replenish(struct ipa_endpoint *endpoint, u32 count) return; }
+ /* If already active, just update the backlog */ + if (test_and_set_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags)) { + if (count) + atomic_add(count, &endpoint->replenish_backlog); + return; + }
while (atomic_dec_not_zero(&endpoint->replenish_backlog)) if (ipa_endpoint_replenish_one(endpoint)) goto try_again_later; + + clear_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags); + if (count) atomic_add(count, &endpoint->replenish_backlog);
return;
try_again_later: + clear_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags); + /* The last one didn't succeed, so fix the backlog */ backlog = atomic_inc_return(&endpoint->replenish_backlog);
@@ -1473,6 +1484,7 @@ static void ipa_endpoint_setup_one(struct ipa_endpoint *endpoint) * backlog is the same as the maximum outstanding TREs. */ clear_bit(IPA_REPLENISH_ENABLED, endpoint->replenish_flags); + clear_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags); atomic_set(&endpoint->replenish_saved, gsi_channel_tre_max(gsi, endpoint->channel_id)); atomic_set(&endpoint->replenish_backlog, 0); diff --git a/drivers/net/ipa/ipa_endpoint.h b/drivers/net/ipa/ipa_endpoint.h index ffae393500d4f..823c4a1296587 100644 --- a/drivers/net/ipa/ipa_endpoint.h +++ b/drivers/net/ipa/ipa_endpoint.h @@ -43,10 +43,12 @@ enum ipa_endpoint_name { * enum ipa_replenish_flag: RX buffer replenish flags * * @IPA_REPLENISH_ENABLED: Whether receive buffer replenishing is enabled + * @IPA_REPLENISH_ACTIVE: Whether replenishing is underway * @IPA_REPLENISH_COUNT: Number of defined replenish flags */ enum ipa_replenish_flag { IPA_REPLENISH_ENABLED, + IPA_REPLENISH_ACTIVE, IPA_REPLENISH_COUNT, /* Number of flags (must be last) */ };