linux-stable.git/drivers/s390/crypto, branch linux-4.6.y

s390/zcrypt: Fix cryptographic device id in kernel messages

2016-01-26T11:46:58+00:00

Currently, on card response failures a combination of card domain and
domain id is recorded in the kernel messages.

According to the message description only the card id will be recorded.
The domain id is not relevant, since the whole card including all domains
is set offline.

Signed-off-by: Ingo Tuchscherer 
Signed-off-by: Martin Schwidefsky

s390: Delete unnecessary checks before the function call "debug_unregister"

2015-11-27T08:24:16+00:00

The debug_unregister() function performs also input parameter validation.
Thus the test around the calls is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring 
Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

s390/zcrypt: Fix AP queue handling if queue is full

2015-11-27T08:23:29+00:00

When the AP queue depth of requests was reached additional requests
have been ignored. These request are stuck in the request queue.

The AP queue handling now push the next waiting request into the
queue after fetching a previous serviced and finished reply.

Signed-off-by: Ingo Tuchscherer 
Acked-by: Martin Schwidefsky 
Acked-by: Harald Freudenberger 
Signed-off-by: Martin Schwidefsky

s390/zcrypt: Fix initialisation when zcrypt is built-in

2015-11-11T12:56:34+00:00

ap_bus and zcrypt_api assumed module information to always be present
and initialisation to be done in module loading order (symbol
dependencies). These assumptions don't hold if zcrypt is built-in;
THIS_MODULE will be NULL in this case and init call order is linker
order, i.e. Makefile order.

Fix initialisation order by ordering the object files in the Makefile
according to their dependencies, like the module loader would do.

Fix message type registration by using a dedicated "name" field rather
than piggy-backing on the module ("owner") information. There's no
change to the requirement that module name and msgtype name are
identical. The existing name macros are used.

We don't need any special code for dealing with the drivers being
built-in; the generic module support code already does the right
thing.

Test results:
1. CONFIG_MODULES=y, CONFIG_ZCRYPT=y

   KVM: boots, no /sys/bus/ap (expected)
   LPAR with CEX5: boots, /sys/bus/ap/devices/card*/type present

2. CONFIG_MODULES=y, CONFIG_ZCRYPT=m=:

   KVM: boots, loading zcrypt_cex4 (and ap) fails (expected)
   LPAR with CEX5: boots, loading =zcrypt_cex4= succeeds,
   /sys/bus/ap/devices/card*/type present after explicit module
   loading

3. CONFIG_MODULES unset, CONFIG_ZCRYPT=y:
   KVM: boots, no /sys/bus/ap (expected)
   LPAR with CEX5: boots, /sys/bus/ap/devices/card*/type present

No further testing (user-space functionality) was done.

Fixes: 3b6245fd303f ("s390/zcrypt: Separate msgtype implementation from card modules.")
Signed-off-by: Sascha Silbe 
Signed-off-by: Martin Schwidefsky

s390/zcrypt: Fix kernel crash on systems without AP bus support

2015-11-11T12:56:30+00:00

On systems without AP bus (e.g. KVM) the kernel crashes during init
calls when zcrypt is built-in:

kernel BUG at drivers/base/driver.c:153!
illegal operation: 0001 ilc:1 [#1] SMP
Modules linked in:
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.2.0+ #221
task: 0000000010a40000 ti: 0000000010a48000 task.ti:0000000010a48000
Krnl PSW : 0704c00180000000 0000000000592bd6(driver_register+0x106/0x140)
           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 EA:3
           0000000000000012 0000000000000000 0000000000c45328 0000000000c44e30
           00000000009ef63c 000000000067f598 0000000000cf3c58 0000000000000000
           000000000000007b 0000000000cb1030 0000000000000002 0000000000000000
           0000000000ca8580 0000000010306700 00000000001001d8 0000000010a4bd88
Krnl Code: 0000000000592bc6: f0b00004ebcf	srp 4(12,%r0),3023(%r14),0
           0000000000592bcc: f0a0000407f4       srp     4(11,%r0),2036,0
          #0000000000592bd2: a7f40001           brc     15,592bd4
          >0000000000592bd6: e330d0000004       lg      %r3,0(%r13)
           0000000000592bdc: c0200021edfd       larl    %r2,9d07d6
           0000000000592be2: c0e500126d8f       brasl   %r14,7e0700
           0000000000592be8: e330d0080004       lg      %r3,8(%r13)
           0000000000592bee: a7f4ffab           brc     15,592b44
Call Trace:
([<00000000001001c8>] do_one_initcall+0x90/0x1d0)
 [<0000000000c6dd34>] kernel_init_freeable+0x1e4/0x2a0
 [<00000000007db53a>] kernel_init+0x2a/0x120
 [<00000000007e8ece>] kernel_thread_starter+0x6/0xc
 [<00000000007e8ec8>] kernel_thread_starter+0x0/0xc
Last Breaking-Event-Address:
 [<0000000000592bd2>] driver_register+0x102/0x140

When zcrypt is built as a module, the module loader ensures that the
driver modules cannot be loaded if the AP bus module returns an error
during initialisation. But if zcrypt and the driver are built-in, the
driver is getting initialised even if the AP bus initialisation
failed. The driver invokes ap_driver_register() during initialisation,
which then causes operations on uninitialised data structures to be
performed.

Explicitly protect ap_driver_register() by introducing an
"initialised" flag that gets set iff the AP bus initialisation was
successful. When the AP bus initialisation failed,
ap_driver_register() will error out with -ENODEV, causing the driver
initialisation to fail as well.

Test results:
1. Inside KVM (no AP bus), zcrypt built-in

   Boots. /sys/bus/ap not present (expected).

2. Inside KVM (no AP bus), zcrypt as module

   Boots. Loading zcrypt_cex4 fails because loading ap_bus fails
   (expected).

3. On LPAR with CEX5, zcrypt built-in

   Boots. /sys/bus/ap/devices/card* present but .../card*/type missing
   (i.e. zcrypt_device_register() fails, unrelated issue).

4. On LPAR with CEX5, zcrypt as module

   Boots. Loading zcrypt_cex4 successful,
   /sys/bus/ap/devices/card*/type present. No further testing
   (user-space functionality) was done.

Signed-off-by: Sascha Silbe 
Signed-off-by: Martin Schwidefsky

s390/zcrypt: use system work queue for ap_scan_bus

2015-10-14T12:32:25+00:00

There is a system work queue system_long_wq for long running work.
Use this work queue for the AP bus scan loop.

Reviewd-by: Ingo Tuchscherer 
Signed-off-by: Martin Schwidefsky

s390/zcrypt: remove support for PCICC and PCICA cards

2015-10-14T12:32:24+00:00

Remove the code for really old crypt cards, PCICC and PCICA.
These cards have been out of service for several years.

Reviewd-by: Ingo Tuchscherer 
Signed-off-by: Martin Schwidefsky

s390/zcrypt: introduce state machine for the AP bus

2015-10-14T12:32:23+00:00

Replace the two fields 'unregistered' and 'reset' with a device
state with 5 possible values. Introduce two events for the AP devices,
device poll and device timeout. With the state machine it is easier
to deal with device initialization and suspend/resume. Device polling
is simpler as well, the arkane 'flags' passing is gone.

Reviewd-by: Ingo Tuchscherer 
Signed-off-by: Martin Schwidefsky

s390/zcrypt: use explicit return code for flushed requests

2015-10-14T12:32:22+00:00

If a AP device is removed while messages are still pending, the requests
are cancelled by calling the message receive function with an error pointer
for the reply. The message type receive handler recognize this and create
a fake hardware error TYPE82_RSP_CODE / REP82_ERROR_MACHINE_FAILURE.
The message with the hardware error then causes a printk and a return
code of -EAGAIN.

Replace the intricate scheme with an explicit return code for this sitation
and avoid the error message.

Reviewd-by: Ingo Tuchscherer 
Signed-off-by: Martin Schwidefsky

s390/zcrypt: cleanup AP bus timer code

2015-10-14T12:32:21+00:00

Set the configuration timer at the end of the ap_scan_bus function.
Make use of setup_timer and remove some unnecessary add_timer, mod_timer
and del_timer_sync calls. Replace the complicated timer_pending, mod_timer
and add_timer code in ap_config_time_store with a simple mod_timer.

Reviewd-by: Ingo Tuchscherer 
Signed-off-by: Martin Schwidefsky