Re: [PATCH 1/2] powerpc/pseries: Failure on removing device node
From: Nathan Fontenot <hidden>
Date: 2014-08-11 14:16:08
On 08/11/2014 04:16 AM, Gavin Shan wrote:
While running command "drmgr -c phb -r -s 'PHB 528'", following backtrace jumped out because the target device node isn't marked with OF_DETACHED by of_detach_node(), which caused by error returned from memory hotplug related reconfig notifier when disabling CONFIG_MEMORY_HOTREMOVE. The patch fixes it.
Could you provide some more context here. Your comment claims that you hit an error while trying to remove a PHB, but the fix you provided is for memory hotplug. This changes the rturn code to zero which usually inidcates success except that your comment states you disabled memory hotplug remove. I think the fix we need to have here is to update the version of pseries_remove_mem_node() when CONFIG_MEMORY_HOTREMOVE is disabled to validate that the node is a memory node and return the proper value instead of just returning -EOPNOTSUPP in all cases. The pseries_remove_mem_node() routine when memory removed is enabled already does this. -Nathan
quoted hunk ↗ jump to hunk
ERROR: Bad of_node_put() on /pci@800000020000210/ethernet@0 CPU: 14 PID: 2252 Comm: drmgr Tainted: G W 3.16.0+ #427 Call Trace: [c000000012a776a0] [c000000000013d9c] .show_stack+0x88/0x148 (unreliable) [c000000012a77750] [c00000000083cd34] .dump_stack+0x7c/0x9c [c000000012a777d0] [c0000000006807c4] .of_node_release+0x58/0xe0 [c000000012a77860] [c00000000038a7d0] .kobject_release+0x174/0x1b8 [c000000012a77900] [c00000000038a884] .kobject_put+0x70/0x78 [c000000012a77980] [c000000000681680] .of_node_put+0x28/0x34 [c000000012a77a00] [c000000000681ea8] .__of_get_next_child+0x64/0x70 [c000000012a77a90] [c000000000682138] .of_find_node_by_path+0x1b8/0x20c [c000000012a77b40] [c000000000051840] .ofdt_write+0x308/0x688 [c000000012a77c20] [c000000000238430] .proc_reg_write+0xb8/0xd4 [c000000012a77cd0] [c0000000001cbeac] .vfs_write+0xec/0x1f8 [c000000012a77d70] [c0000000001cc3b0] .SyS_write+0x58/0xa0 [c000000012a77e30] [c00000000000a064] syscall_exit+0x0/0x98 Cc: stable@vger.kernel.org Signed-off-by: Gavin Shan <redacted> --- arch/powerpc/platforms/pseries/hotplug-memory.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c index 7995135..24abc5c 100644 --- a/arch/powerpc/platforms/pseries/hotplug-memory.c +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c@@ -146,7 +146,7 @@ static inline int pseries_remove_memblock(unsigned long base, } static inline int pseries_remove_mem_node(struct device_node *np) { - return -EOPNOTSUPP; + return 0; } #endif /* CONFIG_MEMORY_HOTREMOVE */