/openbmc/linux/Documentation/ABI/testing/ |
H A D | sysfs-class-cxl | diff 70b565bbdb911023373e035225ab10077e4ab937 Fri Oct 14 04:38:36 CDT 2016 Vaibhav Jain <vaibhav@linux.vnet.ibm.com> cxl: Prevent adapter reset if an active context exists
This patch prevents resetting the cxl adapter via sysfs in presence of one or more active cxl_context on it. This protects against an unrecoverable error caused by PSL owning a dirty cache line even after reset and host tries to touch the same cache line. In case a force reset of the card is required irrespective of any active contexts, the int value -1 can be stored in the 'reset' sysfs attribute of the card.
The patch introduces a new atomic_t member named contexts_num inside struct cxl that holds the number of active context attached to the card , which is checked against '0' before proceeding with the reset. To prevent against a race condition where a context is activated just after reset check is performed, the contexts_num is atomically set to '-1' after reset-check to indicate that no more contexts can be activated on the card anymore.
Before activating a context we atomically test if contexts_num is non-negative and if so, increment its value by one. In case the value of contexts_num is negative then it indicates that the card is about to be reset and context activation is error-ed out at that point.
Fixes: 62fa19d4b4fd ("cxl: Add ability to reset the card") Cc: stable@vger.kernel.org # v4.0+ Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
/openbmc/linux/drivers/misc/cxl/ |
H A D | sysfs.c | diff 70b565bbdb911023373e035225ab10077e4ab937 Fri Oct 14 04:38:36 CDT 2016 Vaibhav Jain <vaibhav@linux.vnet.ibm.com> cxl: Prevent adapter reset if an active context exists
This patch prevents resetting the cxl adapter via sysfs in presence of one or more active cxl_context on it. This protects against an unrecoverable error caused by PSL owning a dirty cache line even after reset and host tries to touch the same cache line. In case a force reset of the card is required irrespective of any active contexts, the int value -1 can be stored in the 'reset' sysfs attribute of the card.
The patch introduces a new atomic_t member named contexts_num inside struct cxl that holds the number of active context attached to the card , which is checked against '0' before proceeding with the reset. To prevent against a race condition where a context is activated just after reset check is performed, the contexts_num is atomically set to '-1' after reset-check to indicate that no more contexts can be activated on the card anymore.
Before activating a context we atomically test if contexts_num is non-negative and if so, increment its value by one. In case the value of contexts_num is negative then it indicates that the card is about to be reset and context activation is error-ed out at that point.
Fixes: 62fa19d4b4fd ("cxl: Add ability to reset the card") Cc: stable@vger.kernel.org # v4.0+ Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
H A D | main.c | diff 70b565bbdb911023373e035225ab10077e4ab937 Fri Oct 14 04:38:36 CDT 2016 Vaibhav Jain <vaibhav@linux.vnet.ibm.com> cxl: Prevent adapter reset if an active context exists
This patch prevents resetting the cxl adapter via sysfs in presence of one or more active cxl_context on it. This protects against an unrecoverable error caused by PSL owning a dirty cache line even after reset and host tries to touch the same cache line. In case a force reset of the card is required irrespective of any active contexts, the int value -1 can be stored in the 'reset' sysfs attribute of the card.
The patch introduces a new atomic_t member named contexts_num inside struct cxl that holds the number of active context attached to the card , which is checked against '0' before proceeding with the reset. To prevent against a race condition where a context is activated just after reset check is performed, the contexts_num is atomically set to '-1' after reset-check to indicate that no more contexts can be activated on the card anymore.
Before activating a context we atomically test if contexts_num is non-negative and if so, increment its value by one. In case the value of contexts_num is negative then it indicates that the card is about to be reset and context activation is error-ed out at that point.
Fixes: 62fa19d4b4fd ("cxl: Add ability to reset the card") Cc: stable@vger.kernel.org # v4.0+ Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
H A D | guest.c | diff 70b565bbdb911023373e035225ab10077e4ab937 Fri Oct 14 04:38:36 CDT 2016 Vaibhav Jain <vaibhav@linux.vnet.ibm.com> cxl: Prevent adapter reset if an active context exists
This patch prevents resetting the cxl adapter via sysfs in presence of one or more active cxl_context on it. This protects against an unrecoverable error caused by PSL owning a dirty cache line even after reset and host tries to touch the same cache line. In case a force reset of the card is required irrespective of any active contexts, the int value -1 can be stored in the 'reset' sysfs attribute of the card.
The patch introduces a new atomic_t member named contexts_num inside struct cxl that holds the number of active context attached to the card , which is checked against '0' before proceeding with the reset. To prevent against a race condition where a context is activated just after reset check is performed, the contexts_num is atomically set to '-1' after reset-check to indicate that no more contexts can be activated on the card anymore.
Before activating a context we atomically test if contexts_num is non-negative and if so, increment its value by one. In case the value of contexts_num is negative then it indicates that the card is about to be reset and context activation is error-ed out at that point.
Fixes: 62fa19d4b4fd ("cxl: Add ability to reset the card") Cc: stable@vger.kernel.org # v4.0+ Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
H A D | api.c | diff 70b565bbdb911023373e035225ab10077e4ab937 Fri Oct 14 04:38:36 CDT 2016 Vaibhav Jain <vaibhav@linux.vnet.ibm.com> cxl: Prevent adapter reset if an active context exists
This patch prevents resetting the cxl adapter via sysfs in presence of one or more active cxl_context on it. This protects against an unrecoverable error caused by PSL owning a dirty cache line even after reset and host tries to touch the same cache line. In case a force reset of the card is required irrespective of any active contexts, the int value -1 can be stored in the 'reset' sysfs attribute of the card.
The patch introduces a new atomic_t member named contexts_num inside struct cxl that holds the number of active context attached to the card , which is checked against '0' before proceeding with the reset. To prevent against a race condition where a context is activated just after reset check is performed, the contexts_num is atomically set to '-1' after reset-check to indicate that no more contexts can be activated on the card anymore.
Before activating a context we atomically test if contexts_num is non-negative and if so, increment its value by one. In case the value of contexts_num is negative then it indicates that the card is about to be reset and context activation is error-ed out at that point.
Fixes: 62fa19d4b4fd ("cxl: Add ability to reset the card") Cc: stable@vger.kernel.org # v4.0+ Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
H A D | file.c | diff 70b565bbdb911023373e035225ab10077e4ab937 Fri Oct 14 04:38:36 CDT 2016 Vaibhav Jain <vaibhav@linux.vnet.ibm.com> cxl: Prevent adapter reset if an active context exists
This patch prevents resetting the cxl adapter via sysfs in presence of one or more active cxl_context on it. This protects against an unrecoverable error caused by PSL owning a dirty cache line even after reset and host tries to touch the same cache line. In case a force reset of the card is required irrespective of any active contexts, the int value -1 can be stored in the 'reset' sysfs attribute of the card.
The patch introduces a new atomic_t member named contexts_num inside struct cxl that holds the number of active context attached to the card , which is checked against '0' before proceeding with the reset. To prevent against a race condition where a context is activated just after reset check is performed, the contexts_num is atomically set to '-1' after reset-check to indicate that no more contexts can be activated on the card anymore.
Before activating a context we atomically test if contexts_num is non-negative and if so, increment its value by one. In case the value of contexts_num is negative then it indicates that the card is about to be reset and context activation is error-ed out at that point.
Fixes: 62fa19d4b4fd ("cxl: Add ability to reset the card") Cc: stable@vger.kernel.org # v4.0+ Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
H A D | context.c | diff 70b565bbdb911023373e035225ab10077e4ab937 Fri Oct 14 04:38:36 CDT 2016 Vaibhav Jain <vaibhav@linux.vnet.ibm.com> cxl: Prevent adapter reset if an active context exists
This patch prevents resetting the cxl adapter via sysfs in presence of one or more active cxl_context on it. This protects against an unrecoverable error caused by PSL owning a dirty cache line even after reset and host tries to touch the same cache line. In case a force reset of the card is required irrespective of any active contexts, the int value -1 can be stored in the 'reset' sysfs attribute of the card.
The patch introduces a new atomic_t member named contexts_num inside struct cxl that holds the number of active context attached to the card , which is checked against '0' before proceeding with the reset. To prevent against a race condition where a context is activated just after reset check is performed, the contexts_num is atomically set to '-1' after reset-check to indicate that no more contexts can be activated on the card anymore.
Before activating a context we atomically test if contexts_num is non-negative and if so, increment its value by one. In case the value of contexts_num is negative then it indicates that the card is about to be reset and context activation is error-ed out at that point.
Fixes: 62fa19d4b4fd ("cxl: Add ability to reset the card") Cc: stable@vger.kernel.org # v4.0+ Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
H A D | cxl.h | diff 70b565bbdb911023373e035225ab10077e4ab937 Fri Oct 14 04:38:36 CDT 2016 Vaibhav Jain <vaibhav@linux.vnet.ibm.com> cxl: Prevent adapter reset if an active context exists
This patch prevents resetting the cxl adapter via sysfs in presence of one or more active cxl_context on it. This protects against an unrecoverable error caused by PSL owning a dirty cache line even after reset and host tries to touch the same cache line. In case a force reset of the card is required irrespective of any active contexts, the int value -1 can be stored in the 'reset' sysfs attribute of the card.
The patch introduces a new atomic_t member named contexts_num inside struct cxl that holds the number of active context attached to the card , which is checked against '0' before proceeding with the reset. To prevent against a race condition where a context is activated just after reset check is performed, the contexts_num is atomically set to '-1' after reset-check to indicate that no more contexts can be activated on the card anymore.
Before activating a context we atomically test if contexts_num is non-negative and if so, increment its value by one. In case the value of contexts_num is negative then it indicates that the card is about to be reset and context activation is error-ed out at that point.
Fixes: 62fa19d4b4fd ("cxl: Add ability to reset the card") Cc: stable@vger.kernel.org # v4.0+ Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
H A D | pci.c | diff 70b565bbdb911023373e035225ab10077e4ab937 Fri Oct 14 04:38:36 CDT 2016 Vaibhav Jain <vaibhav@linux.vnet.ibm.com> cxl: Prevent adapter reset if an active context exists
This patch prevents resetting the cxl adapter via sysfs in presence of one or more active cxl_context on it. This protects against an unrecoverable error caused by PSL owning a dirty cache line even after reset and host tries to touch the same cache line. In case a force reset of the card is required irrespective of any active contexts, the int value -1 can be stored in the 'reset' sysfs attribute of the card.
The patch introduces a new atomic_t member named contexts_num inside struct cxl that holds the number of active context attached to the card , which is checked against '0' before proceeding with the reset. To prevent against a race condition where a context is activated just after reset check is performed, the contexts_num is atomically set to '-1' after reset-check to indicate that no more contexts can be activated on the card anymore.
Before activating a context we atomically test if contexts_num is non-negative and if so, increment its value by one. In case the value of contexts_num is negative then it indicates that the card is about to be reset and context activation is error-ed out at that point.
Fixes: 62fa19d4b4fd ("cxl: Add ability to reset the card") Cc: stable@vger.kernel.org # v4.0+ Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|