Re: HDD problem, software bug, bios bug, or hardware ?

[Mikael Pettersson <mikpe@it.uu.se>]

Adko Branil writes:
 > After updating bios no more crashes happened, i tested it many times
 > on heavy HDD IO loads, with many kernels (including CONFIG_PREEMPT
 > kernels). But now if enable "Cool'n' Quiet" option in bios, 
 > CONFIG_PREEMPT_VOLUNTARY kernel with passed "nosmp" at boot time,
 > crashes during boot process with kernel panic, while  CONFIG_PREEMPT
 > kernlel without "nosmp" works fine  - but it is another story i think,
 > should not be related with the crashes when it was old bios, and i
 > think it is probably "nosmp" the reason. (i have never changed cpu
 > frequency of this cpu at all) When "Cool'n' Quiet" is disabled, the
 > system works perfectly adequately with all kind of kernels i tried.
 > Except that this warning message in dmesg still appears (if it is
 > problem at all). I put here this message for "nosmp" case as well,
 > kernel is 3.5.2:
 > 
 > [    1.912494] =================================
 > [    1.912494] [ INFO: inconsistent lock state ]
 > [    1.912494] 3.5.2 #4 Not tainted
 > [    1.912494] ---------------------------------
 > [    1.912494] inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.
 > [    1.912494] swapper/0/1 [HC1[1]:SC1[1]:HE0:SE0] takes:
 > [    1.912494]  (&(&host->lock)->rlock){?.+...}, at: [<ffffffff818f4e47>] ata_bmdma_interrupt+0x27/0x1d0
 > [    1.912494] {HARDIRQ-ON-W} state was registered at:
 > [    1.912494]   [<ffffffff810998fb>] __lock_acquire+0x61b/0x1af0
 > [    1.912494]   [<ffffffff8109b31a>] lock_acquire+0x8a/0x110
 > [    1.912494]   [<ffffffff81b4d051>] _raw_spin_lock+0x31/0x40
 > [    1.912494]   [<ffffffff8190b3c5>] pdc_sata_hardreset+0x85/0x100

Please try the patch below, which implements the fix I described a
week ago. It's for 3.6-rc4 but should work in any recent kernel.
Without this patch one of my test machines always throws a lockdep
warning involving pdc_sata_hardreset and pdc_interrupt during bootup,
but with the patch the warning is gone, as expected.

If it works for you I'll add your Tested-by: and submit it properly.

/Mikael

--- linux-3.6-rc4/drivers/ata/sata_promise.c.~1~	2012-09-08 12:18:24.000000000 +0200
+++ linux-3.6-rc4/drivers/ata/sata_promise.c	2012-09-08 17:55:49.000000000 +0200
@@ -147,6 +147,10 @@ struct pdc_port_priv {
 	dma_addr_t		pkt_dma;
 };
 
+struct pdc_host_priv {
+	spinlock_t hard_reset_lock;
+};
+
 static int pdc_sata_scr_read(struct ata_link *link, unsigned int sc_reg, u32 *val);
 static int pdc_sata_scr_write(struct ata_link *link, unsigned int sc_reg, u32 val);
 static int pdc_ata_init_one(struct pci_dev *pdev, const struct pci_device_id *ent);
@@ -801,9 +805,10 @@ static void pdc_hard_reset_port(struct a
 	void __iomem *host_mmio = ap->host->iomap[PDC_MMIO_BAR];
 	void __iomem *pcictl_b1_mmio = host_mmio + PDC_PCI_CTL + 1;
 	unsigned int ata_no = pdc_ata_port_to_ata_no(ap);
+	struct pdc_host_priv *hpriv = ap->host->private_data;
 	u8 tmp;
 
-	spin_lock(&ap->host->lock);
+	spin_lock(&hpriv->hard_reset_lock);
 
 	tmp = readb(pcictl_b1_mmio);
 	tmp &= ~(0x10 << ata_no);
@@ -814,7 +819,7 @@ static void pdc_hard_reset_port(struct a
 	writeb(tmp, pcictl_b1_mmio);
 	readb(pcictl_b1_mmio); /* flush */
 
-	spin_unlock(&ap->host->lock);
+	spin_unlock(&hpriv->hard_reset_lock);
 }
 
 static int pdc_sata_hardreset(struct ata_link *link, unsigned int *class,
@@ -1182,6 +1187,7 @@ static int pdc_ata_init_one(struct pci_d
 	const struct ata_port_info *pi = &pdc_port_info[ent->driver_data];
 	const struct ata_port_info *ppi[PDC_MAX_PORTS];
 	struct ata_host *host;
+	struct pdc_host_priv *hpriv;
 	void __iomem *host_mmio;
 	int n_ports, i, rc;
 	int is_sataii_tx4;
@@ -1218,6 +1224,11 @@ static int pdc_ata_init_one(struct pci_d
 		dev_err(&pdev->dev, "failed to allocate host\n");
 		return -ENOMEM;
 	}
+	hpriv = devm_kzalloc(&pdev->dev, sizeof *hpriv, GFP_KERNEL);
+	if (!hpriv)
+		return -ENOMEM;
+	spin_lock_init(&hpriv->hard_reset_lock);
+	host->private_data = hpriv;
 	host->iomap = pcim_iomap_table(pdev);
 
 	is_sataii_tx4 = pdc_is_sataii_tx4(pi->flags);