Hello,

Please picked up this patch for linux 4.4 and 4.9. Compiled/tested without problem.

[ Upstream commit d312fefea8387503375f728855c9a62de20c9665 ]

From: Ard Biesheuvel ard.biesheuvel@linaro.org Date: Mon, 2 Oct 2017 19:31:24 +0100 Subject: [PATCH] ahci: don't ignore result code of ahci_reset_controller()

ahci_pci_reset_controller() calls ahci_reset_controller(), which may fail, but ignores the result code and always returns success. This may result in failures like below

ahci 0000:02:00.0: version 3.0 ahci 0000:02:00.0: enabling device (0000 -> 0003) ahci 0000:02:00.0: SSS flag set, parallel bus scan disabled ahci 0000:02:00.0: controller reset failed (0xffffffff) ahci 0000:02:00.0: failed to stop engine (-5) ... repeated many times ... ahci 0000:02:00.0: failed to stop engine (-5) Unable to handle kernel paging request at virtual address ffff0000093f9018 ... PC is at ahci_stop_engine+0x5c/0xd8 [libahci] LR is at ahci_deinit_port.constprop.12+0x1c/0xc0 [libahci] ... [<ffff000000a17014>] ahci_stop_engine+0x5c/0xd8 [libahci] [<ffff000000a196b4>] ahci_deinit_port.constprop.12+0x1c/0xc0 [libahci] [<ffff000000a197d8>] ahci_init_controller+0x80/0x168 [libahci] [<ffff000000a260f8>] ahci_pci_init_controller+0x60/0x68 [ahci] [<ffff000000a26f94>] ahci_init_one+0x75c/0xd88 [ahci] [<ffff000008430324>] local_pci_probe+0x3c/0xb8 [<ffff000008431728>] pci_device_probe+0x138/0x170 [<ffff000008585e54>] driver_probe_device+0x2dc/0x458 [<ffff0000085860e4>] __driver_attach+0x114/0x118 [<ffff000008583ca8>] bus_for_each_dev+0x60/0xa0 [<ffff000008585638>] driver_attach+0x20/0x28 [<ffff0000085850b0>] bus_add_driver+0x1f0/0x2a8 [<ffff000008586ae0>] driver_register+0x60/0xf8 [<ffff00000842f9b4>] __pci_register_driver+0x3c/0x48 [<ffff000000a3001c>] ahci_pci_driver_init+0x1c/0x1000 [ahci] [<ffff000008083918>] do_one_initcall+0x38/0x120

where an obvious hardware level failure results in an unnecessary 15 second delay and a subsequent crash.

So record the result code of ahci_reset_controller() and relay it, rather than ignoring it.

Signed-off-by: Ard Biesheuvel ard.biesheuvel@linaro.org Signed-off-by: Tejun Heo tj@kernel.org --- drivers/ata/ahci.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index cb9b0e9090e3b..9f78bb03bb763 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -621,8 +621,11 @@ static void ahci_pci_save_initial_config(struct pci_dev *pdev, static int ahci_pci_reset_controller(struct ata_host *host) { struct pci_dev *pdev = to_pci_dev(host->dev); + int rc;

- ahci_reset_controller(host); + rc = ahci_reset_controller(host); + if (rc) + return rc;

if (pdev->vendor == PCI_VENDOR_ID_INTEL) { struct ahci_host_priv *hpriv = host->private_data;