[PATCH v3] soc: fsl: dpio: Get the cpumask through cpumask_of(cpu)

Subsystems: freescale soc drivers, the rest · Maintainers: Christophe Leroy, Linus Torvalds

STALE2163d

2 messages, 2 authors, 2020-11-24 · open the first message on its own page

[PATCH v3] soc: fsl: dpio: Get the cpumask through cpumask_of(cpu)

From: Yi Wang <hidden>
Date: 2020-10-20 02:15:41

From: Hao Si <redacted>

The local variable 'cpumask_t mask' is in the stack memory, and its address
is assigned to 'desc->affinity' in 'irq_set_affinity_hint()'.
But the memory area where this variable is located is at risk of being
modified.

During LTP testing, the following error was generated:

Unable to handle kernel paging request at virtual address ffff000012e9b790
Mem abort info:
  ESR = 0x96000007
  Exception class = DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
Data abort info:
  ISV = 0, ISS = 0x00000007
  CM = 0, WnR = 0
swapper pgtable: 4k pages, 48-bit VAs, pgdp = 0000000075ac5e07
[ffff000012e9b790] pgd=00000027dbffe003, pud=00000027dbffd003,
pmd=00000027b6d61003, pte=0000000000000000
Internal error: Oops: 96000007 [#1] PREEMPT SMP
Modules linked in: xt_conntrack
Process read_all (pid: 20171, stack limit = 0x0000000044ea4095)
CPU: 14 PID: 20171 Comm: read_all Tainted: G    B   W
Hardware name: NXP Layerscape LX2160ARDB (DT)
pstate: 80000085 (Nzcv daIf -PAN -UAO)
pc : irq_affinity_hint_proc_show+0x54/0xb0
lr : irq_affinity_hint_proc_show+0x4c/0xb0
sp : ffff00001138bc10
x29: ffff00001138bc10 x28: 0000ffffd131d1e0
x27: 00000000007000c0 x26: ffff8025b9480dc0
x25: ffff8025b9480da8 x24: 00000000000003ff
x23: ffff8027334f8300 x22: ffff80272e97d000
x21: ffff80272e97d0b0 x20: ffff8025b9480d80
x19: ffff000009a49000 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000
x15: 0000000000000000 x14: 0000000000000000
x13: 0000000000000000 x12: 0000000000000040
x11: 0000000000000000 x10: ffff802735b79b88

40 more lines

diff --git a/drivers/soc/fsl/dpio/dpio-driver.c b/drivers/soc/fsl/dpio/dpio-driver.c
index 7b642c3..7f397b4 100644
--- a/drivers/soc/fsl/dpio/dpio-driver.c
+++ b/drivers/soc/fsl/dpio/dpio-driver.c

@@ -95,7 +95,6 @@ static int register_dpio_irq_handlers(struct fsl_mc_device *dpio_dev, int cpu)
 {
 	int error;
 	struct fsl_mc_device_irq *irq;
-	cpumask_t mask;
 
 	irq = dpio_dev->irqs[0];
 	error = devm_request_irq(&dpio_dev->dev,

@@ -112,9 +111,7 @@ static int register_dpio_irq_handlers(struct fsl_mc_device *dpio_dev, int cpu)
 	}
 
 	/* set the affinity hint */
-	cpumask_clear(&mask);
-	cpumask_set_cpu(cpu, &mask);
-	if (irq_set_affinity_hint(irq->msi_desc->irq, &mask))
+	if (irq_set_affinity_hint(irq->msi_desc->irq, cpumask_of(cpu)))
 		dev_err(&dpio_dev->dev,
 			"irq_set_affinity failed irq %d cpu %d\n",
 			irq->msi_desc->irq, cpu);

-- 
2.15.2

Re: [PATCH v3] soc: fsl: dpio: Get the cpumask through cpumask_of(cpu)

From: Li Yang <hidden>
Date: 2020-11-24 01:26:16

On Mon, Oct 19, 2020 at 9:15 PM Yi Wang [off-list ref] wrote:

From: Hao Si <redacted>

The local variable 'cpumask_t mask' is in the stack memory, and its address
is assigned to 'desc->affinity' in 'irq_set_affinity_hint()'.
But the memory area where this variable is located is at risk of being
modified.

During LTP testing, the following error was generated:

Unable to handle kernel paging request at virtual address ffff000012e9b790
Mem abort info:
  ESR = 0x96000007
  Exception class = DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
Data abort info:
  ISV = 0, ISS = 0x00000007
  CM = 0, WnR = 0
swapper pgtable: 4k pages, 48-bit VAs, pgdp = 0000000075ac5e07
[ffff000012e9b790] pgd=00000027dbffe003, pud=00000027dbffd003,
pmd=00000027b6d61003, pte=0000000000000000
Internal error: Oops: 96000007 [#1] PREEMPT SMP
Modules linked in: xt_conntrack
Process read_all (pid: 20171, stack limit = 0x0000000044ea4095)
CPU: 14 PID: 20171 Comm: read_all Tainted: G    B   W
Hardware name: NXP Layerscape LX2160ARDB (DT)
pstate: 80000085 (Nzcv daIf -PAN -UAO)
pc : irq_affinity_hint_proc_show+0x54/0xb0
lr : irq_affinity_hint_proc_show+0x4c/0xb0
sp : ffff00001138bc10
x29: ffff00001138bc10 x28: 0000ffffd131d1e0
x27: 00000000007000c0 x26: ffff8025b9480dc0
x25: ffff8025b9480da8 x24: 00000000000003ff
x23: ffff8027334f8300 x22: ffff80272e97d000
x21: ffff80272e97d0b0 x20: ffff8025b9480d80
x19: ffff000009a49000 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000
x15: 0000000000000000 x14: 0000000000000000
x13: 0000000000000000 x12: 0000000000000040

32 more quoted lines

Applied for fix.  Thanks.

quoted hunk

---
v3: Use cpumask_of(cpu) to get the pre-defined cpumask in the static
cpu_bit_bitmap array.
v2: Place 'cpumask_t mask' in the driver's private data and while at it,
rename it to cpu_mask.

 drivers/soc/fsl/dpio/dpio-driver.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/soc/fsl/dpio/dpio-driver.c b/drivers/soc/fsl/dpio/dpio-driver.c
index 7b642c3..7f397b4 100644
--- a/drivers/soc/fsl/dpio/dpio-driver.c
+++ b/drivers/soc/fsl/dpio/dpio-driver.c

@@ -95,7 +95,6 @@ static int register_dpio_irq_handlers(struct fsl_mc_device *dpio_dev, int cpu)
 {
        int error;
        struct fsl_mc_device_irq *irq;
-       cpumask_t mask;

        irq = dpio_dev->irqs[0];
        error = devm_request_irq(&dpio_dev->dev,

@@ -112,9 +111,7 @@ static int register_dpio_irq_handlers(struct fsl_mc_device *dpio_dev, int cpu)
        }

        /* set the affinity hint */
-       cpumask_clear(&mask);
-       cpumask_set_cpu(cpu, &mask);
-       if (irq_set_affinity_hint(irq->msi_desc->irq, &mask))
+       if (irq_set_affinity_hint(irq->msi_desc->irq, cpumask_of(cpu)))
                dev_err(&dpio_dev->dev,
                        "irq_set_affinity failed irq %d cpu %d\n",
                        irq->msi_desc->irq, cpu);
--

2.15.2

`h`	back out one level
`j`	next message in thread
`k`	previous message in thread
`l`	drill in
`Esc`	close help / fold thread tree
`?`	toggle this help