diff options
author | Paul Gortmaker | 2013-02-04 10:49:42 +0100 |
---|---|---|
committer | David S. Miller | 2013-02-05 03:08:01 +0100 |
commit | 7c1e7e99ab8fac65222cfc0a2cc35f3678086cfa (patch) | |
tree | b44a099570301072075c56bca58ee68f9fb613d8 /drivers/cpufreq/speedstep-smi.c | |
parent | ipcomp: Mark as netns_ok. (diff) | |
download | kernel-qcow2-linux-7c1e7e99ab8fac65222cfc0a2cc35f3678086cfa.tar.gz kernel-qcow2-linux-7c1e7e99ab8fac65222cfc0a2cc35f3678086cfa.tar.xz kernel-qcow2-linux-7c1e7e99ab8fac65222cfc0a2cc35f3678086cfa.zip |
gianfar: dont conditionally alloc Rx/Err irq structs
Commit ee873fda3bec7c668407b837fc5519eb961fcd37
"gianfar: Pack struct gfar_priv_grp into three cachelines"
causes the following null dereference at driver init on sbc8548:
libphy: Freescale PowerQUICC MII Bus: probed
Unable to handle kernel paging request for data at address 0x00000000
Faulting instruction address: 0xc01d6a38
Oops: Kernel access of bad area, sig: 11 [#1]
[...]
NIP [c01d6a38] gfar_parse_group+0x228/0x280
LR [c01d6a34] gfar_parse_group+0x224/0x280
Call Trace:
[ef82dd60] [c01d6a34] gfar_parse_group+0x224/0x280 (unreliable)
[ef82dd90] [c01d73a4] gfar_probe+0x284/0xfe0
The reason is that the commit also changed the allocation of the
Rx and error handling irq structs to be skipped for !MQ_MG_MODE.
In the !MQ_MG_MODE case, only the Tx irq struct is allocated.
Digging further, we see that MQ_MG_MODE is set only if we find
the OF compatible string "fsl,etsec2".
A quick grep in the dts directory shows lots of boards that support
Rx/Tx/Err, but without this specific compat string. And hence they
go after the unallocated Rx/Error structs and cause the above oops.
Hence such a change can not be deployed until all the dts files
are updated and sufficiently deployed. Further, the optimization
is of limited value, since the kmalloc'd struct in question has only
a single unsigned int, and an (IFNAMSIZ + 6) sized string.
Note that no changes to the freeing code are needed here, as it
already did an unconditional free of Rx/Tx/Error gfar_irqinfo.
Cc: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/cpufreq/speedstep-smi.c')
0 files changed, 0 insertions, 0 deletions