Skip to contentSkip to conversation

Patch "iommu/amd: Fix boot warning when device 00:00.0 is not iommu covered" has been added to the 4.4-stable tree

PATCH [email protected] 1 participant 1 message Mar 4, 2016

Subsystems (2)
Stable branch IOMMU
lore
Share & tools
lore

[email protected]

author maintainer Applied
#0 lore raw

This is a note to let you know that I've just added the patch titled

iommu/amd: Fix boot warning when device 00:00.0 is not iommu covered

to the 4.4-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:

     iommu-amd-fix-boot-warning-when-device-00-00.0-is-not-iommu-covered.patch

and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

Quoted 1 line

From 38e45d02ea9f194b89d6bf41e52ccafc8e2c2b47 Mon Sep 17 00:00:00 2001

From: Suravee Suthikulpanit <[email protected]>
Date: Tue, 23 Feb 2016 13:03:30 +0100
Subject: iommu/amd: Fix boot warning when device 00:00.0 is not iommu covered

From: Suravee Suthikulpanit <[email protected]>

commit 38e45d02ea9f194b89d6bf41e52ccafc8e2c2b47 upstream.

The setup code for the performance counters in the AMD IOMMU driver tests whether the counters can be written. It tests to setup a counter for device 00:00.0, which fails on systems where this particular device is not covered by the IOMMU.

Fix this by not relying on device 00:00.0 but only on the IOMMU being present.

Signed-off-by Suravee Suthikulpanit <[email protected]>
Signed-off-by Joerg Roedel <[email protected]>
Signed-off-by Greg Kroah-Hartman <[email protected]>
---
 drivers/iommu/amd_iommu_init.c |   34 ++++++++++++++++++++++------------
 1 file changed, 22 insertions(+), 12 deletions(-)
drivers/iommu/amd_iommu_init.c +22 -12
@@ -228,6 +228,10 @@ static int amd_iommu_enable_interrupts(v
 static int __init iommu_go_to_state(enum iommu_init_state state);
 static void init_device_table_dma(void);
 
+static int iommu_pc_get_set_reg_val(struct amd_iommu *iommu,
+				    u8 bank, u8 cntr, u8 fxn,
+				    u64 *value, bool is_write);
+
 static inline void update_last_devid(u16 devid)
 {
 	if (devid > amd_iommu_last_bdf)

@@ -1170,8 +1174,8 @@ static void init_iommu_perf_ctr(struct a
 	amd_iommu_pc_present = true;
 
 	/* Check if the performance counters can be written to */
-	if ((0 != amd_iommu_pc_get_set_reg_val(0, 0, 0, 0, &val, true)) ||
-	    (0 != amd_iommu_pc_get_set_reg_val(0, 0, 0, 0, &val2, false)) ||
+	if ((0 != iommu_pc_get_set_reg_val(iommu, 0, 0, 0, &val, true)) ||
+	    (0 != iommu_pc_get_set_reg_val(iommu, 0, 0, 0, &val2, false)) ||
 	    (val != val2)) {
 		pr_err("AMD-Vi: Unable to write to IOMMU perf counter.\n");
 		amd_iommu_pc_present = false;

@@ -2312,22 +2316,15 @@ u8 amd_iommu_pc_get_max_counters(u16 dev
 }
 EXPORT_SYMBOL(amd_iommu_pc_get_max_counters);
 
-int amd_iommu_pc_get_set_reg_val(u16 devid, u8 bank, u8 cntr, u8 fxn,
+static int iommu_pc_get_set_reg_val(struct amd_iommu *iommu,
+				    u8 bank, u8 cntr, u8 fxn,
 				    u64 *value, bool is_write)
 {
-	struct amd_iommu *iommu;
 	u32 offset;
 	u32 max_offset_lim;
 
-	/* Make sure the IOMMU PC resource is available */
-	if (!amd_iommu_pc_present)
-		return -ENODEV;
-
-	/* Locate the iommu associated with the device ID */
-	iommu = amd_iommu_rlookup_table[devid];
-
 	/* Check for valid iommu and pc register indexing */
-	if (WARN_ON((iommu == NULL) || (fxn > 0x28) || (fxn & 7)))
+	if (WARN_ON((fxn > 0x28) || (fxn & 7)))
 		return -ENODEV;
 
 	offset = (u32)(((0x40|bank) << 12) | (cntr << 8) | fxn);

@@ -2351,3 +2348,16 @@ int amd_iommu_pc_get_set_reg_val(u16 dev
 	return 0;
 }
 EXPORT_SYMBOL(amd_iommu_pc_get_set_reg_val);
+
+int amd_iommu_pc_get_set_reg_val(u16 devid, u8 bank, u8 cntr, u8 fxn,
+				    u64 *value, bool is_write)
+{
+	struct amd_iommu *iommu = amd_iommu_rlookup_table[devid];
+
+	/* Make sure the IOMMU PC resource is available */
+	if (!amd_iommu_pc_present || iommu == NULL)
+		return -ENODEV;
+
+	return iommu_pc_get_set_reg_val(iommu, bank, cntr, fxn,
+					value, is_write);
+}

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/iommu-amd-fix-boot-warning-when-device-00-00.0-is-not-iommu-covered.patch