This is a note to let you know that I've just added the patch titled net: ipa: disable HOLB drop when updating timer to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-ipa-disable-holb-drop-when-updating-timer.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 9f9dce3fa02594b45aae12f423dfce94771e5a76 Author: Alex Elder <elder@xxxxxxxxxx> Date: Fri Nov 12 16:22:10 2021 -0600 net: ipa: disable HOLB drop when updating timer [ Upstream commit 816316cacad2b5abd5b41423cf04e4845239abd4 ] The head-of-line blocking timer should only be modified when head-of-line drop is disabled. One of the steps in recovering from a modem crash is to enable dropping of packets with timeout of 0 (immediate). We don't know how the modem configured its endpoints, so before we program the timer, we need to ensure HOL_BLOCK is disabled. Fixes: 84f9bd12d46db ("soc: qcom: ipa: IPA endpoints") Signed-off-by: Alex Elder <elder@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ipa/ipa_endpoint.c b/drivers/net/ipa/ipa_endpoint.c index b7ec9b3ce3129..b0637774ad29c 100644 --- a/drivers/net/ipa/ipa_endpoint.c +++ b/drivers/net/ipa/ipa_endpoint.c @@ -703,6 +703,7 @@ static void ipa_endpoint_init_hol_block_timer(struct ipa_endpoint *endpoint, u32 offset; u32 val; + /* This should only be changed when HOL_BLOCK_EN is disabled */ offset = IPA_REG_ENDP_INIT_HOL_BLOCK_TIMER_N_OFFSET(endpoint_id); val = ipa_reg_init_hol_block_timer_val(ipa, microseconds); iowrite32(val, ipa->reg_virt + offset); @@ -733,6 +734,7 @@ void ipa_endpoint_modem_hol_block_clear_all(struct ipa *ipa) if (endpoint->toward_ipa || endpoint->ee_id != GSI_EE_MODEM) continue; + ipa_endpoint_init_hol_block_enable(endpoint, false); ipa_endpoint_init_hol_block_timer(endpoint, 0); ipa_endpoint_init_hol_block_enable(endpoint, true); }