From patchwork Mon Jan 18 10:09:42 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Ahmed S. Darwish" X-Patchwork-Id: 12028291 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BA86EC433DB for ; Mon, 18 Jan 2021 21:24:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7198722D6F for ; Mon, 18 Jan 2021 21:24:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2437765AbhARVXc (ORCPT ); Mon, 18 Jan 2021 16:23:32 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:54990 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389624AbhARKLN (ORCPT ); Mon, 18 Jan 2021 05:11:13 -0500 From: "Ahmed S. Darwish" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1610964630; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=oXp58ztUPQpe2lDu9I5bDZMNMwvtBAwE8TiJPqiuvCM=; b=KrSbafBpEUMukNZoCo4iLwtn95xctagBaRD/HSr5feTNfOn7KLbwrHQqjTzQR84N+KTSko s95Oal9oII21QPhvSXPL7AelUYlvcKmPgSpksPsPtjHcCWv1Wxgp3rlVHpmxTusyOhn/XR 0IoOILhijnnmmcLMR8GgttkaBK+n4nzhqCp2UcOx94fiT3vdGWTQsj08ocAvd5vgGALRUQ dpW2Yg7hYNVz0FtPl/6XPdKdlZUGITctRz/PY8AdGtpHQ7G5PIPKsAB4TQ5YbGiRPpocU9 kFRFo9UuVMYzuYZ/cyxZyr6K8MpCNZVmuyJv5LDVnoiR06l1zWldNSR9bs148w== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1610964630; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=oXp58ztUPQpe2lDu9I5bDZMNMwvtBAwE8TiJPqiuvCM=; b=y80DiuCzoMP2vvuroUZW8RgJS3b2cd3CVH8tx8q46jJbDovhohn/sWj1R5KxP1I7Fut3qc OSWN+UH19RlWPxBQ== To: "James E.J. Bottomley" , "Martin K. Petersen" , Christoph Hellwig , John Garry , Jason Yan , Daniel Wagner , Artur Paszkiewicz , Jack Wang Cc: linux-scsi@vger.kernel.org, LKML , Thomas Gleixner , "Sebastian A. Siewior" , "Ahmed S. Darwish" Subject: [PATCH v3 06/19] scsi: isci: port: link up: Pass gfp_t flags Date: Mon, 18 Jan 2021 11:09:42 +0100 Message-Id: <20210118100955.1761652-7-a.darwish@linutronix.de> In-Reply-To: <20210118100955.1761652-1-a.darwish@linutronix.de> References: <20210118100955.1761652-1-a.darwish@linutronix.de> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Use the new libsas event notifiers API, which requires callers to explicitly pass the gfp_t memory allocation flags. libsas sas_notify_port_event() is called from isci_port_link_up(). Below is the context analysis for all of its call chains: host.c: isci_host_init() (@) spin_lock_irq(isci_host::scic_lock) -> sci_controller_initialize(), atomic (*) -> port_config.c: sci_port_configuration_agent_initialize() -> sci_mpc_agent_validate_phy_configuration() -> port.c: sci_port_add_phy() -> sci_port_general_link_up_handler() -> sci_port_activate_phy() -> isci_port_link_up() port_config.c: apc_agent_timeout(), atomic, timer callback (*) -> sci_apc_agent_configure_ports() -> port.c: sci_port_add_phy() -> sci_port_general_link_up_handler() -> sci_port_activate_phy() -> isci_port_link_up() phy.c: enter SCI state: *SCI_PHY_SUB_FINAL* # Cont. from [1] -> phy.c: sci_phy_starting_final_substate_enter() -> phy.c: sci_change_state(SCI_PHY_READY) -> enter SCI state: *SCI_PHY_READY* -> phy.c: sci_phy_ready_state_enter() -> host.c: sci_controller_link_up() -> .link_up_handler() == port_config.c: sci_apc_agent_link_up() -> port.c: sci_port_link_up() -> (continue at [A]) == port_config.c: sci_mpc_agent_link_up() -> port.c: sci_port_link_up() -> (continue at [A]) port_config.c: mpc_agent_timeout(), atomic, timer callback (*) spin_lock_irqsave(isci_host::scic_lock, ) -> ->link_up_handler() == port_config.c: sci_apc_agent_link_up() -> port.c: sci_port_link_up() -> (continue at [A]) == port_config.c: sci_mpc_agent_link_up() -> port.c: sci_port_link_up() -> (continue at [A]) [A] port.c: sci_port_link_up() -> sci_port_activate_phy() -> isci_port_link_up() -> sci_port_general_link_up_handler() -> sci_port_activate_phy() -> isci_port_link_up() [1] Call chains for entering SCI state: *SCI_PHY_SUB_FINAL* ----------------------------------------------------------- host.c: power_control_timeout(), atomic, timer callback (*) spin_lock_irqsave(isci_host::scic_lock, ) -> phy.c: sci_phy_consume_power_handler() -> phy.c: sci_change_state(SCI_PHY_SUB_FINAL) host.c: sci_controller_error_handler(): atomic, irq handler (*) OR host.c: sci_controller_completion_handler(), atomic, tasklet (*) -> sci_controller_process_completions() -> sci_controller_unsolicited_frame() -> phy.c: sci_phy_frame_handler() -> sci_change_state(SCI_PHY_SUB_AWAIT_SAS_POWER) -> sci_phy_starting_await_sas_power_substate_enter() -> host.c: sci_controller_power_control_queue_insert() -> phy.c: sci_phy_consume_power_handler() -> sci_change_state(SCI_PHY_SUB_FINAL) -> sci_change_state(SCI_PHY_SUB_FINAL) -> sci_controller_event_completion() -> phy.c: sci_phy_event_handler() -> sci_phy_start_sata_link_training() -> sci_change_state(SCI_PHY_SUB_AWAIT_SATA_POWER) -> sci_phy_starting_await_sata_power_substate_enter -> host.c: sci_controller_power_control_queue_insert() -> phy.c: sci_phy_consume_power_handler() -> sci_change_state(SCI_PHY_SUB_FINAL) As can be seen from the "(*)" markers above, all the call-chains are atomic. Pass GFP_ATOMIC to libsas port event notifier. Note, the now-replaced libsas APIs used in_interrupt() to implicitly decide which memory allocation type to use. This was only partially correct, as it fails to choose the correct GFP flags when just preemption or interrupts are disabled. Such buggy code paths are marked with "(@)" in the call chains above. Fixes: 1c393b970e0f ("scsi: libsas: Use dynamic alloced work to avoid sas event lost") Signed-off-by: Ahmed S. Darwish Reviewed-by: John Garry Cc: Artur Paszkiewicz --- drivers/scsi/isci/port.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/isci/port.c b/drivers/scsi/isci/port.c index a3c58718c260..10136ae466e2 100644 --- a/drivers/scsi/isci/port.c +++ b/drivers/scsi/isci/port.c @@ -223,7 +223,8 @@ static void isci_port_link_up(struct isci_host *isci_host, /* Notify libsas that we have an address frame, if indeed * we've found an SSP, SMP, or STP target */ if (success) - sas_notify_port_event(&iphy->sas_phy, PORTE_BYTES_DMAED); + sas_notify_port_event_gfp(&iphy->sas_phy, + PORTE_BYTES_DMAED, GFP_ATOMIC); }