* [PATCH] powerpc/pmem: Fix kernel crash due to wrong range value usage in flush_dcache_range
@ 2019-12-04 5:29 Aneesh Kumar K.V
2019-12-04 13:30 ` Michael Ellerman
2019-12-04 13:48 ` Sachin Sant
0 siblings, 2 replies; 3+ messages in thread
From: Aneesh Kumar K.V @ 2019-12-04 5:29 UTC (permalink / raw)
To: mpe; +Cc: Sachin Sant, Aneesh Kumar K.V, linuxppc-dev
This patch fix the below kernel crash.
BUG: Unable to handle kernel data access on read at 0xc000000380000000
Faulting instruction address: 0xc00000000008b6f0
cpu 0x5: Vector: 300 (Data Access) at [c0000000d8587790]
pc: c00000000008b6f0: arch_remove_memory+0x150/0x210
lr: c00000000008b720: arch_remove_memory+0x180/0x210
sp: c0000000d8587a20
msr: 800000000280b033
dar: c000000380000000
dsisr: 40000000
current = 0xc0000000d8558600
paca = 0xc00000000fff8f00 irqmask: 0x03 irq_happened: 0x01
pid = 1220, comm = ndctl
enter ? for help
memunmap_pages+0x33c/0x410
devm_action_release+0x30/0x50
release_nodes+0x30c/0x3a0
device_release_driver_internal+0x178/0x240
unbind_store+0x74/0x190
drv_attr_store+0x44/0x60
sysfs_kf_write+0x74/0xa0
kernfs_fop_write+0x1b0/0x260
__vfs_write+0x3c/0x70
vfs_write+0xe4/0x200
ksys_write+0x7c/0x140
system_call+0x5c/0x68
Fixes: 076265907cf9 ("powerpc: Chunk calls to flush_dcache_range in arch_*_memory")
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/mm/mem.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index ad299e72ec30..9488b63dfc87 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -121,7 +121,7 @@ static void flush_dcache_range_chunked(unsigned long start, unsigned long stop,
unsigned long i;
for (i = start; i < stop; i += chunk) {
- flush_dcache_range(i, min(stop, start + chunk));
+ flush_dcache_range(i, min(stop, i + chunk));
cond_resched();
}
}
--
2.23.0
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH] powerpc/pmem: Fix kernel crash due to wrong range value usage in flush_dcache_range
2019-12-04 5:29 [PATCH] powerpc/pmem: Fix kernel crash due to wrong range value usage in flush_dcache_range Aneesh Kumar K.V
@ 2019-12-04 13:30 ` Michael Ellerman
2019-12-04 13:48 ` Sachin Sant
1 sibling, 0 replies; 3+ messages in thread
From: Michael Ellerman @ 2019-12-04 13:30 UTC (permalink / raw)
To: Aneesh Kumar K.V; +Cc: Sachin Sant, Aneesh Kumar K.V, linuxppc-dev
On Wed, 2019-12-04 at 05:29:09 UTC, "Aneesh Kumar K.V" wrote:
> This patch fix the below kernel crash.
>
> BUG: Unable to handle kernel data access on read at 0xc000000380000000
> Faulting instruction address: 0xc00000000008b6f0
> cpu 0x5: Vector: 300 (Data Access) at [c0000000d8587790]
> pc: c00000000008b6f0: arch_remove_memory+0x150/0x210
> lr: c00000000008b720: arch_remove_memory+0x180/0x210
> sp: c0000000d8587a20
> msr: 800000000280b033
> dar: c000000380000000
> dsisr: 40000000
> current = 0xc0000000d8558600
> paca = 0xc00000000fff8f00 irqmask: 0x03 irq_happened: 0x01
> pid = 1220, comm = ndctl
> enter ? for help
> memunmap_pages+0x33c/0x410
> devm_action_release+0x30/0x50
> release_nodes+0x30c/0x3a0
> device_release_driver_internal+0x178/0x240
> unbind_store+0x74/0x190
> drv_attr_store+0x44/0x60
> sysfs_kf_write+0x74/0xa0
> kernfs_fop_write+0x1b0/0x260
> __vfs_write+0x3c/0x70
> vfs_write+0xe4/0x200
> ksys_write+0x7c/0x140
> system_call+0x5c/0x68
>
> Fixes: 076265907cf9 ("powerpc: Chunk calls to flush_dcache_range in arch_*_memory")
> Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Applied to powerpc fixes, thanks.
https://git.kernel.org/powerpc/c/6f4679b956741d2da6ad3ebb738cbe1264ac8781
cheers
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH] powerpc/pmem: Fix kernel crash due to wrong range value usage in flush_dcache_range
2019-12-04 5:29 [PATCH] powerpc/pmem: Fix kernel crash due to wrong range value usage in flush_dcache_range Aneesh Kumar K.V
2019-12-04 13:30 ` Michael Ellerman
@ 2019-12-04 13:48 ` Sachin Sant
1 sibling, 0 replies; 3+ messages in thread
From: Sachin Sant @ 2019-12-04 13:48 UTC (permalink / raw)
To: Aneesh Kumar K.V; +Cc: linuxppc-dev
>
> Fixes: 076265907cf9 ("powerpc: Chunk calls to flush_dcache_range in arch_*_memory")
> Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
> ---
> arch/powerpc/mm/mem.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
It took a while to setup environment on a replacement machine.
Was able to test the fix. With this fix applied I no longer see the problem.
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Thanks
-Sachin
> diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
> index ad299e72ec30..9488b63dfc87 100644
> --- a/arch/powerpc/mm/mem.c
> +++ b/arch/powerpc/mm/mem.c
> @@ -121,7 +121,7 @@ static void flush_dcache_range_chunked(unsigned long start, unsigned long stop,
> unsigned long i;
>
> for (i = start; i < stop; i += chunk) {
> - flush_dcache_range(i, min(stop, start + chunk));
> + flush_dcache_range(i, min(stop, i + chunk));
> cond_resched();
> }
> }
> --
> 2.23.0
>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2019-12-04 13:59 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-12-04 5:29 [PATCH] powerpc/pmem: Fix kernel crash due to wrong range value usage in flush_dcache_range Aneesh Kumar K.V
2019-12-04 13:30 ` Michael Ellerman
2019-12-04 13:48 ` Sachin Sant
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).