* [PATCH 2/4] hwmon: (pc87427) Use request_muxed_region for Super-IO accesses
2019-04-04 18:33 [PATCH 1/4] hwmon: (f71805f) Use request_muxed_region for Super-IO accesses Guenter Roeck
@ 2019-04-04 18:33 ` Guenter Roeck
2019-04-05 7:46 ` John Garry
2019-04-04 18:33 ` [PATCH 3/4] hwmon: (smsc47b397) " Guenter Roeck
` (2 subsequent siblings)
3 siblings, 1 reply; 11+ messages in thread
From: Guenter Roeck @ 2019-04-04 18:33 UTC (permalink / raw)
To: Hardware Monitoring; +Cc: Jean Delvare, Guenter Roeck, John Garry
Super-IO accesses may fail on a system with no or unmapped LPC bus.
Also, other drivers may attempt to access the LPC bus at the same time,
resulting in undefined behavior.
Use request_muxed_region() to ensure that IO access on the requested
address space is supported, and to ensure that access by multiple drivers
is synchronized.
Fixes: ba224e2c4f0a7 ("hwmon: New PC87427 hardware monitoring driver")
Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reported-by: John Garry <john.garry@huawei.com>
Cc: John Garry <john.garry@huawei.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
drivers/hwmon/pc87427.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/drivers/hwmon/pc87427.c b/drivers/hwmon/pc87427.c
index d1a3f2040c00..58eee8fa3e6d 100644
--- a/drivers/hwmon/pc87427.c
+++ b/drivers/hwmon/pc87427.c
@@ -106,6 +106,13 @@ static const char *logdev_str[2] = { DRVNAME " FMC", DRVNAME " HMC" };
#define LD_IN 1
#define LD_TEMP 1
+static inline int superio_enter(int sioaddr)
+{
+ if (!request_muxed_region(sioaddr, 2, DRVNAME))
+ return -EBUSY;
+ return 0;
+}
+
static inline void superio_outb(int sioaddr, int reg, int val)
{
outb(reg, sioaddr);
@@ -122,6 +129,7 @@ static inline void superio_exit(int sioaddr)
{
outb(0x02, sioaddr);
outb(0x02, sioaddr + 1);
+ release_region(sioaddr, 2);
}
/*
@@ -1195,7 +1203,11 @@ static int __init pc87427_find(int sioaddr, struct pc87427_sio_data *sio_data)
{
u16 val;
u8 cfg, cfg_b;
- int i, err = 0;
+ int i, err;
+
+ err = superio_enter(sioaddr);
+ if (err)
+ return err;
/* Identify device */
val = force_id ? force_id : superio_inb(sioaddr, SIOREG_DEVID);
--
2.7.4
^ permalink raw reply related [flat|nested] 11+ messages in thread* Re: [PATCH 2/4] hwmon: (pc87427) Use request_muxed_region for Super-IO accesses
2019-04-04 18:33 ` [PATCH 2/4] hwmon: (pc87427) " Guenter Roeck
@ 2019-04-05 7:46 ` John Garry
0 siblings, 0 replies; 11+ messages in thread
From: John Garry @ 2019-04-05 7:46 UTC (permalink / raw)
To: Guenter Roeck, Hardware Monitoring; +Cc: Jean Delvare, Linux PCI
On 04/04/2019 19:33, Guenter Roeck wrote:
> Super-IO accesses may fail on a system with no or unmapped LPC bus.
>
> Also, other drivers may attempt to access the LPC bus at the same time,
> resulting in undefined behavior.
>
> Use request_muxed_region() to ensure that IO access on the requested
> address space is supported, and to ensure that access by multiple drivers
> is synchronized.
>
> Fixes: ba224e2c4f0a7 ("hwmon: New PC87427 hardware monitoring driver")
> Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> Reported-by: John Garry <john.garry@huawei.com>
> Cc: John Garry <john.garry@huawei.com>
Acked-by: John Garry <john.garry@huawei.com>
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> ---
> drivers/hwmon/pc87427.c | 14 +++++++++++++-
> 1 file changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hwmon/pc87427.c b/drivers/hwmon/pc87427.c
> index d1a3f2040c00..58eee8fa3e6d 100644
> --- a/drivers/hwmon/pc87427.c
> +++ b/drivers/hwmon/pc87427.c
> @@ -106,6 +106,13 @@ static const char *logdev_str[2] = { DRVNAME " FMC", DRVNAME " HMC" };
> #define LD_IN 1
> #define LD_TEMP 1
>
> +static inline int superio_enter(int sioaddr)
> +{
> + if (!request_muxed_region(sioaddr, 2, DRVNAME))
> + return -EBUSY;
> + return 0;
> +}
> +
> static inline void superio_outb(int sioaddr, int reg, int val)
> {
> outb(reg, sioaddr);
> @@ -122,6 +129,7 @@ static inline void superio_exit(int sioaddr)
> {
> outb(0x02, sioaddr);
> outb(0x02, sioaddr + 1);
> + release_region(sioaddr, 2);
> }
>
> /*
> @@ -1195,7 +1203,11 @@ static int __init pc87427_find(int sioaddr, struct pc87427_sio_data *sio_data)
> {
> u16 val;
> u8 cfg, cfg_b;
> - int i, err = 0;
> + int i, err;
> +
> + err = superio_enter(sioaddr);
> + if (err)
> + return err;
>
> /* Identify device */
> val = force_id ? force_id : superio_inb(sioaddr, SIOREG_DEVID);
>
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 3/4] hwmon: (smsc47b397) Use request_muxed_region for Super-IO accesses
2019-04-04 18:33 [PATCH 1/4] hwmon: (f71805f) Use request_muxed_region for Super-IO accesses Guenter Roeck
2019-04-04 18:33 ` [PATCH 2/4] hwmon: (pc87427) " Guenter Roeck
@ 2019-04-04 18:33 ` Guenter Roeck
2019-04-05 7:47 ` John Garry
2019-04-04 18:33 ` [PATCH 4/4] " Guenter Roeck
2019-04-05 7:45 ` [PATCH 1/4] hwmon: (f71805f) " John Garry
3 siblings, 1 reply; 11+ messages in thread
From: Guenter Roeck @ 2019-04-04 18:33 UTC (permalink / raw)
To: Hardware Monitoring; +Cc: Jean Delvare, Guenter Roeck, John Garry
Super-IO accesses may fail on a system with no or unmapped LPC bus.
Also, other drivers may attempt to access the LPC bus at the same time,
resulting in undefined behavior.
Use request_muxed_region() to ensure that IO access on the requested
address space is supported, and to ensure that access by multiple drivers
is synchronized.
Fixes: 8d5d45fb1468 ("I2C: Move hwmon drivers (2/3)")
Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reported-by: John Garry <john.garry@huawei.com>
Cc: John Garry <john.garry@huawei.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
drivers/hwmon/smsc47b397.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/hwmon/smsc47b397.c b/drivers/hwmon/smsc47b397.c
index c0775084dde0..60e193f2e970 100644
--- a/drivers/hwmon/smsc47b397.c
+++ b/drivers/hwmon/smsc47b397.c
@@ -72,14 +72,19 @@ static inline void superio_select(int ld)
superio_outb(0x07, ld);
}
-static inline void superio_enter(void)
+static inline int superio_enter(void)
{
+ if (!request_muxed_region(REG, 2, DRVNAME))
+ return -EBUSY;
+
outb(0x55, REG);
+ return 0;
}
static inline void superio_exit(void)
{
outb(0xAA, REG);
+ release_region(REG, 2);
}
#define SUPERIO_REG_DEVID 0x20
@@ -300,8 +305,12 @@ static int __init smsc47b397_find(void)
u8 id, rev;
char *name;
unsigned short addr;
+ int err;
+
+ err = superio_enter();
+ if (err)
+ return err;
- superio_enter();
id = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
switch (id) {
--
2.7.4
^ permalink raw reply related [flat|nested] 11+ messages in thread* Re: [PATCH 3/4] hwmon: (smsc47b397) Use request_muxed_region for Super-IO accesses
2019-04-04 18:33 ` [PATCH 3/4] hwmon: (smsc47b397) " Guenter Roeck
@ 2019-04-05 7:47 ` John Garry
0 siblings, 0 replies; 11+ messages in thread
From: John Garry @ 2019-04-05 7:47 UTC (permalink / raw)
To: Guenter Roeck, Hardware Monitoring; +Cc: Jean Delvare, Linux PCI
On 04/04/2019 19:33, Guenter Roeck wrote:
> Super-IO accesses may fail on a system with no or unmapped LPC bus.
>
> Also, other drivers may attempt to access the LPC bus at the same time,
> resulting in undefined behavior.
>
> Use request_muxed_region() to ensure that IO access on the requested
> address space is supported, and to ensure that access by multiple drivers
> is synchronized.
>
> Fixes: 8d5d45fb1468 ("I2C: Move hwmon drivers (2/3)")
> Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> Reported-by: John Garry <john.garry@huawei.com>
Acked-by: John Garry <john.garry@huawei.com>
> Cc: John Garry <john.garry@huawei.com>
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> ---
> drivers/hwmon/smsc47b397.c | 13 +++++++++++--
> 1 file changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hwmon/smsc47b397.c b/drivers/hwmon/smsc47b397.c
> index c0775084dde0..60e193f2e970 100644
> --- a/drivers/hwmon/smsc47b397.c
> +++ b/drivers/hwmon/smsc47b397.c
> @@ -72,14 +72,19 @@ static inline void superio_select(int ld)
> superio_outb(0x07, ld);
> }
>
> -static inline void superio_enter(void)
> +static inline int superio_enter(void)
> {
> + if (!request_muxed_region(REG, 2, DRVNAME))
> + return -EBUSY;
> +
> outb(0x55, REG);
> + return 0;
> }
>
> static inline void superio_exit(void)
> {
> outb(0xAA, REG);
> + release_region(REG, 2);
> }
>
> #define SUPERIO_REG_DEVID 0x20
> @@ -300,8 +305,12 @@ static int __init smsc47b397_find(void)
> u8 id, rev;
> char *name;
> unsigned short addr;
> + int err;
> +
> + err = superio_enter();
> + if (err)
> + return err;
>
> - superio_enter();
> id = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
>
> switch (id) {
>
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 4/4] hwmon: (smsc47b397) Use request_muxed_region for Super-IO accesses
2019-04-04 18:33 [PATCH 1/4] hwmon: (f71805f) Use request_muxed_region for Super-IO accesses Guenter Roeck
2019-04-04 18:33 ` [PATCH 2/4] hwmon: (pc87427) " Guenter Roeck
2019-04-04 18:33 ` [PATCH 3/4] hwmon: (smsc47b397) " Guenter Roeck
@ 2019-04-04 18:33 ` Guenter Roeck
2019-04-05 7:47 ` John Garry
2019-04-05 7:45 ` [PATCH 1/4] hwmon: (f71805f) " John Garry
3 siblings, 1 reply; 11+ messages in thread
From: Guenter Roeck @ 2019-04-04 18:33 UTC (permalink / raw)
To: Hardware Monitoring; +Cc: Jean Delvare, Guenter Roeck, John Garry
Super-IO accesses may fail on a system with no or unmapped LPC bus.
Also, other drivers may attempt to access the LPC bus at the same time,
resulting in undefined behavior.
Use request_muxed_region() to ensure that IO access on the requested
address space is supported, and to ensure that access by multiple drivers
is synchronized.
Fixes: 8d5d45fb1468 ("I2C: Move hwmon drivers (2/3)")
Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reported-by: John Garry <john.garry@huawei.com>
Cc: John Garry <john.garry@huawei.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
drivers/hwmon/smsc47m1.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/hwmon/smsc47m1.c b/drivers/hwmon/smsc47m1.c
index c7b6a425e2c0..0736ca6a3aee 100644
--- a/drivers/hwmon/smsc47m1.c
+++ b/drivers/hwmon/smsc47m1.c
@@ -73,16 +73,21 @@ superio_inb(int reg)
/* logical device for fans is 0x0A */
#define superio_select() superio_outb(0x07, 0x0A)
-static inline void
+static inline int
superio_enter(void)
{
+ if (!request_muxed_region(REG, 2, DRVNAME))
+ return -EBUSY;
+
outb(0x55, REG);
+ return 0;
}
static inline void
superio_exit(void)
{
outb(0xAA, REG);
+ release_region(REG, 2);
}
#define SUPERIO_REG_ACT 0x30
@@ -531,8 +536,12 @@ static int __init smsc47m1_find(struct smsc47m1_sio_data *sio_data)
{
u8 val;
unsigned short addr;
+ int err;
+
+ err = superio_enter();
+ if (err)
+ return err;
- superio_enter();
val = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
/*
--
2.7.4
^ permalink raw reply related [flat|nested] 11+ messages in thread* Re: [PATCH 4/4] hwmon: (smsc47b397) Use request_muxed_region for Super-IO accesses
2019-04-04 18:33 ` [PATCH 4/4] " Guenter Roeck
@ 2019-04-05 7:47 ` John Garry
2019-04-05 8:46 ` John Garry
0 siblings, 1 reply; 11+ messages in thread
From: John Garry @ 2019-04-05 7:47 UTC (permalink / raw)
To: Guenter Roeck, Hardware Monitoring; +Cc: Jean Delvare, Linux PCI
On 04/04/2019 19:33, Guenter Roeck wrote:
> Super-IO accesses may fail on a system with no or unmapped LPC bus.
>
> Also, other drivers may attempt to access the LPC bus at the same time,
> resulting in undefined behavior.
>
> Use request_muxed_region() to ensure that IO access on the requested
> address space is supported, and to ensure that access by multiple drivers
> is synchronized.
>
> Fixes: 8d5d45fb1468 ("I2C: Move hwmon drivers (2/3)")
> Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> Reported-by: John Garry <john.garry@huawei.com>
> Cc: John Garry <john.garry@huawei.com>
Acked-by: John Garry <john.garry@huawei.com>
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> ---
> drivers/hwmon/smsc47m1.c | 13 +++++++++++--
> 1 file changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hwmon/smsc47m1.c b/drivers/hwmon/smsc47m1.c
> index c7b6a425e2c0..0736ca6a3aee 100644
> --- a/drivers/hwmon/smsc47m1.c
> +++ b/drivers/hwmon/smsc47m1.c
> @@ -73,16 +73,21 @@ superio_inb(int reg)
> /* logical device for fans is 0x0A */
> #define superio_select() superio_outb(0x07, 0x0A)
>
> -static inline void
> +static inline int
> superio_enter(void)
> {
> + if (!request_muxed_region(REG, 2, DRVNAME))
> + return -EBUSY;
> +
> outb(0x55, REG);
> + return 0;
> }
>
> static inline void
> superio_exit(void)
> {
> outb(0xAA, REG);
> + release_region(REG, 2);
> }
>
> #define SUPERIO_REG_ACT 0x30
> @@ -531,8 +536,12 @@ static int __init smsc47m1_find(struct smsc47m1_sio_data *sio_data)
> {
> u8 val;
> unsigned short addr;
> + int err;
> +
> + err = superio_enter();
> + if (err)
> + return err;
>
> - superio_enter();
> val = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
>
> /*
>
^ permalink raw reply [flat|nested] 11+ messages in thread* Re: [PATCH 4/4] hwmon: (smsc47b397) Use request_muxed_region for Super-IO accesses
2019-04-05 7:47 ` John Garry
@ 2019-04-05 8:46 ` John Garry
2019-04-05 13:25 ` Guenter Roeck
0 siblings, 1 reply; 11+ messages in thread
From: John Garry @ 2019-04-05 8:46 UTC (permalink / raw)
To: Guenter Roeck, Hardware Monitoring; +Cc: Jean Delvare, Kefeng Wang
On 05/04/2019 08:47, John Garry wrote:
> On 04/04/2019 19:33, Guenter Roeck wrote:
>> Super-IO accesses may fail on a system with no or unmapped LPC bus.
>>
BTW, these may still require attention:
sch56xx-common
smsc47m1
w83627hf
vt1211
Thanks,
John
>> Also, other drivers may attempt to access the LPC bus at the same time,
>> resulting in undefined behavior.
>>
>> Use request_muxed_region() to ensure that IO access on the requested
>> address space is supported, and to ensure that access by multiple drivers
>> is synchronized.
>>
>> Fixes: 8d5d45fb1468 ("I2C: Move hwmon drivers (2/3)")
>> Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
>> Reported-by: John Garry <john.garry@huawei.com>
>> Cc: John Garry <john.garry@huawei.com>
>
> Acked-by: John Garry <john.garry@huawei.com>
>
>> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
>> ---
>> drivers/hwmon/smsc47m1.c | 13 +++++++++++--
>> 1 file changed, 11 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/hwmon/smsc47m1.c b/drivers/hwmon/smsc47m1.c
>> index c7b6a425e2c0..0736ca6a3aee 100644
>> --- a/drivers/hwmon/smsc47m1.c
>> +++ b/drivers/hwmon/smsc47m1.c
>> @@ -73,16 +73,21 @@ superio_inb(int reg)
>> /* logical device for fans is 0x0A */
>> #define superio_select() superio_outb(0x07, 0x0A)
>>
>> -static inline void
>> +static inline int
>> superio_enter(void)
>> {
>> + if (!request_muxed_region(REG, 2, DRVNAME))
>> + return -EBUSY;
>> +
>> outb(0x55, REG);
>> + return 0;
>> }
>>
>> static inline void
>> superio_exit(void)
>> {
>> outb(0xAA, REG);
>> + release_region(REG, 2);
>> }
>>
>> #define SUPERIO_REG_ACT 0x30
>> @@ -531,8 +536,12 @@ static int __init smsc47m1_find(struct
>> smsc47m1_sio_data *sio_data)
>> {
>> u8 val;
>> unsigned short addr;
>> + int err;
>> +
>> + err = superio_enter();
>> + if (err)
>> + return err;
>>
>> - superio_enter();
>> val = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
>>
>> /*
>>
>
^ permalink raw reply [flat|nested] 11+ messages in thread* Re: [PATCH 4/4] hwmon: (smsc47b397) Use request_muxed_region for Super-IO accesses
2019-04-05 8:46 ` John Garry
@ 2019-04-05 13:25 ` Guenter Roeck
2019-04-05 16:02 ` Guenter Roeck
0 siblings, 1 reply; 11+ messages in thread
From: Guenter Roeck @ 2019-04-05 13:25 UTC (permalink / raw)
To: John Garry, Hardware Monitoring; +Cc: Jean Delvare, Kefeng Wang
On 4/5/19 1:46 AM, John Garry wrote:
> On 05/04/2019 08:47, John Garry wrote:
>> On 04/04/2019 19:33, Guenter Roeck wrote:
>>> Super-IO accesses may fail on a system with no or unmapped LPC bus.
>>>
>
> BTW, these may still require attention:
>
> sch56xx-common
> smsc47m1
Those two already call request_muxed_region() in superio_enter().
Though error handling in the latter is less than perfect - I may send
a patch to fix it.
> w83627hf > vt1211
I missed those two. Patches will follow.
Thanks,
Guenter
>
> Thanks,
> John
>
>>> Also, other drivers may attempt to access the LPC bus at the same time,
>>> resulting in undefined behavior.
>>>
>>> Use request_muxed_region() to ensure that IO access on the requested
>>> address space is supported, and to ensure that access by multiple drivers
>>> is synchronized.
>>>
>>> Fixes: 8d5d45fb1468 ("I2C: Move hwmon drivers (2/3)")
>>> Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
>>> Reported-by: John Garry <john.garry@huawei.com>
>>> Cc: John Garry <john.garry@huawei.com>
>>
>> Acked-by: John Garry <john.garry@huawei.com>
>>
>>> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
>>> ---
>>> drivers/hwmon/smsc47m1.c | 13 +++++++++++--
>>> 1 file changed, 11 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/hwmon/smsc47m1.c b/drivers/hwmon/smsc47m1.c
>>> index c7b6a425e2c0..0736ca6a3aee 100644
>>> --- a/drivers/hwmon/smsc47m1.c
>>> +++ b/drivers/hwmon/smsc47m1.c
>>> @@ -73,16 +73,21 @@ superio_inb(int reg)
>>> /* logical device for fans is 0x0A */
>>> #define superio_select() superio_outb(0x07, 0x0A)
>>>
>>> -static inline void
>>> +static inline int
>>> superio_enter(void)
>>> {
>>> + if (!request_muxed_region(REG, 2, DRVNAME))
>>> + return -EBUSY;
>>> +
>>> outb(0x55, REG);
>>> + return 0;
>>> }
>>>
>>> static inline void
>>> superio_exit(void)
>>> {
>>> outb(0xAA, REG);
>>> + release_region(REG, 2);
>>> }
>>>
>>> #define SUPERIO_REG_ACT 0x30
>>> @@ -531,8 +536,12 @@ static int __init smsc47m1_find(struct
>>> smsc47m1_sio_data *sio_data)
>>> {
>>> u8 val;
>>> unsigned short addr;
>>> + int err;
>>> +
>>> + err = superio_enter();
>>> + if (err)
>>> + return err;
>>>
>>> - superio_enter();
>>> val = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
>>>
>>> /*
>>>
>>
>
>
>
^ permalink raw reply [flat|nested] 11+ messages in thread* Re: [PATCH 4/4] hwmon: (smsc47b397) Use request_muxed_region for Super-IO accesses
2019-04-05 13:25 ` Guenter Roeck
@ 2019-04-05 16:02 ` Guenter Roeck
0 siblings, 0 replies; 11+ messages in thread
From: Guenter Roeck @ 2019-04-05 16:02 UTC (permalink / raw)
To: John Garry, Hardware Monitoring; +Cc: Jean Delvare, Kefeng Wang
On Fri, Apr 05, 2019 at 06:25:13AM -0700, Guenter Roeck wrote:
> On 4/5/19 1:46 AM, John Garry wrote:
> >On 05/04/2019 08:47, John Garry wrote:
> >>On 04/04/2019 19:33, Guenter Roeck wrote:
> >>>Super-IO accesses may fail on a system with no or unmapped LPC bus.
> >>>
> >
> >BTW, these may still require attention:
> >
> >sch56xx-common
> >smsc47m1
>
> Those two already call request_muxed_region() in superio_enter().
> Though error handling in the latter is less than perfect - I may send
> a patch to fix it.
>
... and that was because this patch has the wrong subject, and its error
handling is incomplete. I'll resend.
Guenter
> >w83627hf > vt1211
>
> I missed those two. Patches will follow.
>
> Thanks,
> Guenter
>
> >
> >Thanks,
> >John
> >
> >>>Also, other drivers may attempt to access the LPC bus at the same time,
> >>>resulting in undefined behavior.
> >>>
> >>>Use request_muxed_region() to ensure that IO access on the requested
> >>>address space is supported, and to ensure that access by multiple drivers
> >>>is synchronized.
> >>>
> >>>Fixes: 8d5d45fb1468 ("I2C: Move hwmon drivers (2/3)")
> >>>Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> >>>Reported-by: John Garry <john.garry@huawei.com>
> >>>Cc: John Garry <john.garry@huawei.com>
> >>
> >>Acked-by: John Garry <john.garry@huawei.com>
> >>
> >>>Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> >>>---
> >>> drivers/hwmon/smsc47m1.c | 13 +++++++++++--
> >>> 1 file changed, 11 insertions(+), 2 deletions(-)
> >>>
> >>>diff --git a/drivers/hwmon/smsc47m1.c b/drivers/hwmon/smsc47m1.c
> >>>index c7b6a425e2c0..0736ca6a3aee 100644
> >>>--- a/drivers/hwmon/smsc47m1.c
> >>>+++ b/drivers/hwmon/smsc47m1.c
> >>>@@ -73,16 +73,21 @@ superio_inb(int reg)
> >>> /* logical device for fans is 0x0A */
> >>> #define superio_select() superio_outb(0x07, 0x0A)
> >>>
> >>>-static inline void
> >>>+static inline int
> >>> superio_enter(void)
> >>> {
> >>>+ if (!request_muxed_region(REG, 2, DRVNAME))
> >>>+ return -EBUSY;
> >>>+
> >>> outb(0x55, REG);
> >>>+ return 0;
> >>> }
> >>>
> >>> static inline void
> >>> superio_exit(void)
> >>> {
> >>> outb(0xAA, REG);
> >>>+ release_region(REG, 2);
> >>> }
> >>>
> >>> #define SUPERIO_REG_ACT 0x30
> >>>@@ -531,8 +536,12 @@ static int __init smsc47m1_find(struct
> >>>smsc47m1_sio_data *sio_data)
> >>> {
> >>> u8 val;
> >>> unsigned short addr;
> >>>+ int err;
> >>>+
> >>>+ err = superio_enter();
> >>>+ if (err)
> >>>+ return err;
> >>>
> >>>- superio_enter();
> >>> val = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
> >>>
> >>> /*
> >>>
> >>
> >
> >
> >
>
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 1/4] hwmon: (f71805f) Use request_muxed_region for Super-IO accesses
2019-04-04 18:33 [PATCH 1/4] hwmon: (f71805f) Use request_muxed_region for Super-IO accesses Guenter Roeck
` (2 preceding siblings ...)
2019-04-04 18:33 ` [PATCH 4/4] " Guenter Roeck
@ 2019-04-05 7:45 ` John Garry
3 siblings, 0 replies; 11+ messages in thread
From: John Garry @ 2019-04-05 7:45 UTC (permalink / raw)
To: Guenter Roeck, Hardware Monitoring; +Cc: Jean Delvare, Linux PCI
On 04/04/2019 19:33, Guenter Roeck wrote:
> Super-IO accesses may fail on a system with no or unmapped LPC bus.
>
> Unable to handle kernel paging request at virtual address ffffffbffee0002e
> pgd = ffffffc1d68d4000
> [ffffffbffee0002e] *pgd=0000000000000000, *pud=0000000000000000
> Internal error: Oops: 94000046 [#1] PREEMPT SMP
> Modules linked in: f71805f(+) hwmon
> CPU: 3 PID: 1659 Comm: insmod Not tainted 4.5.0+ #88
> Hardware name: linux,dummy-virt (DT)
> task: ffffffc1f6665400 ti: ffffffc1d6418000 task.ti: ffffffc1d6418000
> PC is at f71805f_find+0x6c/0x358 [f71805f]
>
> Also, other drivers may attempt to access the LPC bus at the same time,
> resulting in undefined behavior.
>
> Use request_muxed_region() to ensure that IO access on the requested
> address space is supported, and to ensure that access by multiple
> drivers is synchronized.
>
> Fixes: e53004e20a58e ("hwmon: New f71805f driver")
> Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> Reported-by: John Garry <john.garry@huawei.com>
> Cc: John Garry <john.garry@huawei.com>
Acked-by: John Garry <john.garry@huawei.com>
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> ---
> drivers/hwmon/f71805f.c | 15 ++++++++++++---
> 1 file changed, 12 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/hwmon/f71805f.c b/drivers/hwmon/f71805f.c
> index 73c681162653..623736d2a7c1 100644
> --- a/drivers/hwmon/f71805f.c
> +++ b/drivers/hwmon/f71805f.c
> @@ -96,17 +96,23 @@ superio_select(int base, int ld)
> outb(ld, base + 1);
> }
>
> -static inline void
> +static inline int
> superio_enter(int base)
> {
> + if (!request_muxed_region(base, 2, DRVNAME))
> + return -EBUSY;
> +
> outb(0x87, base);
> outb(0x87, base);
> +
> + return 0;
> }
>
> static inline void
> superio_exit(int base)
> {
> outb(0xaa, base);
> + release_region(base, 2);
> }
>
> /*
> @@ -1561,7 +1567,7 @@ static int __init f71805f_device_add(unsigned short address,
> static int __init f71805f_find(int sioaddr, unsigned short *address,
> struct f71805f_sio_data *sio_data)
> {
> - int err = -ENODEV;
> + int err;
> u16 devid;
>
> static const char * const names[] = {
> @@ -1569,8 +1575,11 @@ static int __init f71805f_find(int sioaddr, unsigned short *address,
> "F71872F/FG or F71806F/FG",
> };
>
> - superio_enter(sioaddr);
> + err = superio_enter(sioaddr);
> + if (err)
> + return err;
>
> + err = -ENODEV;
> devid = superio_inw(sioaddr, SIO_REG_MANID);
> if (devid != SIO_FINTEK_ID)
> goto exit;
>
^ permalink raw reply [flat|nested] 11+ messages in thread