| Message ID | 20200914165042.96218-4-ldufour@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mm: fix memory to node bad links in sysfs | expand |
On 14.09.20 18:50, Laurent Dufour wrote: > At boot time, or when doing memory hot-add operations, if the links in > sysfs can't be created, the system is still able to run, so just report the > error in the kernel log rather than BUG_ON and potentially make system > unusable because the callpath can be called with locks held. > > Since the number of memory blocks managed could be high, the messages are > rate limited. > > As a consequence, link_mem_sections() has no status to report anymore. > > Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com> > Acked-by: Michal Hocko <mhocko@suse.com> > Cc: David Hildenbrand <david@redhat.com> > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > --- > drivers/base/node.c | 33 +++++++++++++++++++++------------ > include/linux/node.h | 16 +++++++--------- > mm/memory_hotplug.c | 5 ++--- > 3 files changed, 30 insertions(+), 24 deletions(-) > > diff --git a/drivers/base/node.c b/drivers/base/node.c > index 01ee73c9d675..249b2ba6dc81 100644 > --- a/drivers/base/node.c > +++ b/drivers/base/node.c > @@ -761,8 +761,8 @@ static int __ref get_nid_for_pfn(unsigned long pfn) > return pfn_to_nid(pfn); > } > > -static int do_register_memory_block_under_node(int nid, > - struct memory_block *mem_blk) > +static void do_register_memory_block_under_node(int nid, > + struct memory_block *mem_blk) > { > int ret; > > @@ -775,12 +775,19 @@ static int do_register_memory_block_under_node(int nid, > ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj, > &mem_blk->dev.kobj, > kobject_name(&mem_blk->dev.kobj)); > - if (ret) > - return ret; > + if (ret && ret != -EEXIST) > + dev_err_ratelimited(&node_devices[nid]->dev, > + "can't create link to %s in sysfs (%d)\n", > + kobject_name(&mem_blk->dev.kobj), ret); > > - return sysfs_create_link_nowarn(&mem_blk->dev.kobj, > + ret = sysfs_create_link_nowarn(&mem_blk->dev.kobj, > &node_devices[nid]->dev.kobj, > kobject_name(&node_devices[nid]->dev.kobj)); > + if (ret && ret != -EEXIST) > + dev_err_ratelimited(&mem_blk->dev, > + "can't create link to %s in sysfs (%d)\n", > + kobject_name(&node_devices[nid]->dev.kobj), > + ret); > } > > /* register memory section under specified node if it spans that node */ > @@ -817,7 +824,8 @@ static int register_mem_block_under_node_early(struct memory_block *mem_blk, > continue; > > /* The memory block is registered to the first matching node */ > - return do_register_memory_block_under_node(nid, mem_blk); > + do_register_memory_block_under_node(nid, mem_blk); > + return 0; > } > /* mem section does not span the specified node */ > return 0; > @@ -832,7 +840,8 @@ static int register_mem_block_under_node_hotplug(struct memory_block *mem_blk, > { > int nid = *(int *)arg; > > - return do_register_memory_block_under_node(nid, mem_blk); > + do_register_memory_block_under_node(nid, mem_blk); > + return 0; > } > > /* > @@ -850,8 +859,8 @@ void unregister_memory_block_under_nodes(struct memory_block *mem_blk) > kobject_name(&node_devices[mem_blk->nid]->dev.kobj)); > } > > -int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, > - enum meminit_context context) > +void link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, > + enum meminit_context context) > { > walk_memory_blocks_func_t func; > > @@ -860,9 +869,9 @@ int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, > else > func = register_mem_block_under_node_early; > > - return walk_memory_blocks(PFN_PHYS(start_pfn), > - PFN_PHYS(end_pfn - start_pfn), (void *)&nid, > - func); > + walk_memory_blocks(PFN_PHYS(start_pfn), PFN_PHYS(end_pfn - start_pfn), > + (void *)&nid, func); > + return; > } > > #ifdef CONFIG_HUGETLBFS > diff --git a/include/linux/node.h b/include/linux/node.h > index 014ba3ab2efd..8e5a29897936 100644 > --- a/include/linux/node.h > +++ b/include/linux/node.h > @@ -99,15 +99,14 @@ extern struct node *node_devices[]; > typedef void (*node_registration_func_t)(struct node *); > > #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_NUMA) > -int link_mem_sections(int nid, unsigned long start_pfn, > - unsigned long end_pfn, > - enum meminit_context context); > +void link_mem_sections(int nid, unsigned long start_pfn, > + unsigned long end_pfn, > + enum meminit_context context); > #else > -static inline int link_mem_sections(int nid, unsigned long start_pfn, > - unsigned long end_pfn, > - enum meminit_context context) > +static inline void link_mem_sections(int nid, unsigned long start_pfn, > + unsigned long end_pfn, > + enum meminit_context context) > { > - return 0; > } > #endif > > @@ -130,8 +129,7 @@ static inline int register_one_node(int nid) > if (error) > return error; > /* link memory sections under this node */ > - error = link_mem_sections(nid, start_pfn, end_pfn, > - MEMINIT_EARLY); > + link_mem_sections(nid, start_pfn, end_pfn, MEMINIT_EARLY); > } > > return error; > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index 03df20078827..01e01a530d38 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -1080,9 +1080,8 @@ int __ref add_memory_resource(int nid, struct resource *res) > } > > /* link memory sections under this node.*/ > - ret = link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1), > - MEMINIT_HOTPLUG); > - BUG_ON(ret); > + link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1), > + MEMINIT_HOTPLUG); > > /* create new memmap entry */ > if (!strcmp(res->name, "System RAM")) > I just remember that I still have some cleanup patches lying around that rework the whole node onlining on the add_memory() path, being able to fail in a nice way rather than ignoring errors. Anyhow, this is good enough for now Acked-by: David Hildenbrand <david@redhat.com>
Le 15/09/2020 à 09:23, David Hildenbrand a écrit : > On 14.09.20 18:50, Laurent Dufour wrote: >> At boot time, or when doing memory hot-add operations, if the links in >> sysfs can't be created, the system is still able to run, so just report the >> error in the kernel log rather than BUG_ON and potentially make system >> unusable because the callpath can be called with locks held. >> >> Since the number of memory blocks managed could be high, the messages are >> rate limited. >> >> As a consequence, link_mem_sections() has no status to report anymore. >> >> Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com> >> Acked-by: Michal Hocko <mhocko@suse.com> >> Cc: David Hildenbrand <david@redhat.com> >> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> >> --- >> drivers/base/node.c | 33 +++++++++++++++++++++------------ >> include/linux/node.h | 16 +++++++--------- >> mm/memory_hotplug.c | 5 ++--- >> 3 files changed, 30 insertions(+), 24 deletions(-) >> >> diff --git a/drivers/base/node.c b/drivers/base/node.c >> index 01ee73c9d675..249b2ba6dc81 100644 >> --- a/drivers/base/node.c >> +++ b/drivers/base/node.c >> @@ -761,8 +761,8 @@ static int __ref get_nid_for_pfn(unsigned long pfn) >> return pfn_to_nid(pfn); >> } >> >> -static int do_register_memory_block_under_node(int nid, >> - struct memory_block *mem_blk) >> +static void do_register_memory_block_under_node(int nid, >> + struct memory_block *mem_blk) >> { >> int ret; >> >> @@ -775,12 +775,19 @@ static int do_register_memory_block_under_node(int nid, >> ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj, >> &mem_blk->dev.kobj, >> kobject_name(&mem_blk->dev.kobj)); >> - if (ret) >> - return ret; >> + if (ret && ret != -EEXIST) >> + dev_err_ratelimited(&node_devices[nid]->dev, >> + "can't create link to %s in sysfs (%d)\n", >> + kobject_name(&mem_blk->dev.kobj), ret); >> >> - return sysfs_create_link_nowarn(&mem_blk->dev.kobj, >> + ret = sysfs_create_link_nowarn(&mem_blk->dev.kobj, >> &node_devices[nid]->dev.kobj, >> kobject_name(&node_devices[nid]->dev.kobj)); >> + if (ret && ret != -EEXIST) >> + dev_err_ratelimited(&mem_blk->dev, >> + "can't create link to %s in sysfs (%d)\n", >> + kobject_name(&node_devices[nid]->dev.kobj), >> + ret); >> } >> >> /* register memory section under specified node if it spans that node */ >> @@ -817,7 +824,8 @@ static int register_mem_block_under_node_early(struct memory_block *mem_blk, >> continue; >> >> /* The memory block is registered to the first matching node */ >> - return do_register_memory_block_under_node(nid, mem_blk); >> + do_register_memory_block_under_node(nid, mem_blk); >> + return 0; >> } >> /* mem section does not span the specified node */ >> return 0; >> @@ -832,7 +840,8 @@ static int register_mem_block_under_node_hotplug(struct memory_block *mem_blk, >> { >> int nid = *(int *)arg; >> >> - return do_register_memory_block_under_node(nid, mem_blk); >> + do_register_memory_block_under_node(nid, mem_blk); >> + return 0; >> } >> >> /* >> @@ -850,8 +859,8 @@ void unregister_memory_block_under_nodes(struct memory_block *mem_blk) >> kobject_name(&node_devices[mem_blk->nid]->dev.kobj)); >> } >> >> -int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, >> - enum meminit_context context) >> +void link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, >> + enum meminit_context context) >> { >> walk_memory_blocks_func_t func; >> >> @@ -860,9 +869,9 @@ int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, >> else >> func = register_mem_block_under_node_early; >> >> - return walk_memory_blocks(PFN_PHYS(start_pfn), >> - PFN_PHYS(end_pfn - start_pfn), (void *)&nid, >> - func); >> + walk_memory_blocks(PFN_PHYS(start_pfn), PFN_PHYS(end_pfn - start_pfn), >> + (void *)&nid, func); >> + return; >> } >> >> #ifdef CONFIG_HUGETLBFS >> diff --git a/include/linux/node.h b/include/linux/node.h >> index 014ba3ab2efd..8e5a29897936 100644 >> --- a/include/linux/node.h >> +++ b/include/linux/node.h >> @@ -99,15 +99,14 @@ extern struct node *node_devices[]; >> typedef void (*node_registration_func_t)(struct node *); >> >> #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_NUMA) >> -int link_mem_sections(int nid, unsigned long start_pfn, >> - unsigned long end_pfn, >> - enum meminit_context context); >> +void link_mem_sections(int nid, unsigned long start_pfn, >> + unsigned long end_pfn, >> + enum meminit_context context); >> #else >> -static inline int link_mem_sections(int nid, unsigned long start_pfn, >> - unsigned long end_pfn, >> - enum meminit_context context) >> +static inline void link_mem_sections(int nid, unsigned long start_pfn, >> + unsigned long end_pfn, >> + enum meminit_context context) >> { >> - return 0; >> } >> #endif >> >> @@ -130,8 +129,7 @@ static inline int register_one_node(int nid) >> if (error) >> return error; >> /* link memory sections under this node */ >> - error = link_mem_sections(nid, start_pfn, end_pfn, >> - MEMINIT_EARLY); >> + link_mem_sections(nid, start_pfn, end_pfn, MEMINIT_EARLY); >> } >> >> return error; >> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c >> index 03df20078827..01e01a530d38 100644 >> --- a/mm/memory_hotplug.c >> +++ b/mm/memory_hotplug.c >> @@ -1080,9 +1080,8 @@ int __ref add_memory_resource(int nid, struct resource *res) >> } >> >> /* link memory sections under this node.*/ >> - ret = link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1), >> - MEMINIT_HOTPLUG); >> - BUG_ON(ret); >> + link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1), >> + MEMINIT_HOTPLUG); >> >> /* create new memmap entry */ >> if (!strcmp(res->name, "System RAM")) >> > > I just remember that I still have some cleanup patches lying around that > rework the whole node onlining on the add_memory() path, being able to > fail in a nice way rather than ignoring errors. Anyhow, this is good > enough for now > > Acked-by: David Hildenbrand <david@redhat.com> > Thanks David.
diff --git a/drivers/base/node.c b/drivers/base/node.c index 01ee73c9d675..249b2ba6dc81 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -761,8 +761,8 @@ static int __ref get_nid_for_pfn(unsigned long pfn) return pfn_to_nid(pfn); } -static int do_register_memory_block_under_node(int nid, - struct memory_block *mem_blk) +static void do_register_memory_block_under_node(int nid, + struct memory_block *mem_blk) { int ret; @@ -775,12 +775,19 @@ static int do_register_memory_block_under_node(int nid, ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj, &mem_blk->dev.kobj, kobject_name(&mem_blk->dev.kobj)); - if (ret) - return ret; + if (ret && ret != -EEXIST) + dev_err_ratelimited(&node_devices[nid]->dev, + "can't create link to %s in sysfs (%d)\n", + kobject_name(&mem_blk->dev.kobj), ret); - return sysfs_create_link_nowarn(&mem_blk->dev.kobj, + ret = sysfs_create_link_nowarn(&mem_blk->dev.kobj, &node_devices[nid]->dev.kobj, kobject_name(&node_devices[nid]->dev.kobj)); + if (ret && ret != -EEXIST) + dev_err_ratelimited(&mem_blk->dev, + "can't create link to %s in sysfs (%d)\n", + kobject_name(&node_devices[nid]->dev.kobj), + ret); } /* register memory section under specified node if it spans that node */ @@ -817,7 +824,8 @@ static int register_mem_block_under_node_early(struct memory_block *mem_blk, continue; /* The memory block is registered to the first matching node */ - return do_register_memory_block_under_node(nid, mem_blk); + do_register_memory_block_under_node(nid, mem_blk); + return 0; } /* mem section does not span the specified node */ return 0; @@ -832,7 +840,8 @@ static int register_mem_block_under_node_hotplug(struct memory_block *mem_blk, { int nid = *(int *)arg; - return do_register_memory_block_under_node(nid, mem_blk); + do_register_memory_block_under_node(nid, mem_blk); + return 0; } /* @@ -850,8 +859,8 @@ void unregister_memory_block_under_nodes(struct memory_block *mem_blk) kobject_name(&node_devices[mem_blk->nid]->dev.kobj)); } -int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, - enum meminit_context context) +void link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, + enum meminit_context context) { walk_memory_blocks_func_t func; @@ -860,9 +869,9 @@ int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, else func = register_mem_block_under_node_early; - return walk_memory_blocks(PFN_PHYS(start_pfn), - PFN_PHYS(end_pfn - start_pfn), (void *)&nid, - func); + walk_memory_blocks(PFN_PHYS(start_pfn), PFN_PHYS(end_pfn - start_pfn), + (void *)&nid, func); + return; } #ifdef CONFIG_HUGETLBFS diff --git a/include/linux/node.h b/include/linux/node.h index 014ba3ab2efd..8e5a29897936 100644 --- a/include/linux/node.h +++ b/include/linux/node.h @@ -99,15 +99,14 @@ extern struct node *node_devices[]; typedef void (*node_registration_func_t)(struct node *); #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_NUMA) -int link_mem_sections(int nid, unsigned long start_pfn, - unsigned long end_pfn, - enum meminit_context context); +void link_mem_sections(int nid, unsigned long start_pfn, + unsigned long end_pfn, + enum meminit_context context); #else -static inline int link_mem_sections(int nid, unsigned long start_pfn, - unsigned long end_pfn, - enum meminit_context context) +static inline void link_mem_sections(int nid, unsigned long start_pfn, + unsigned long end_pfn, + enum meminit_context context) { - return 0; } #endif @@ -130,8 +129,7 @@ static inline int register_one_node(int nid) if (error) return error; /* link memory sections under this node */ - error = link_mem_sections(nid, start_pfn, end_pfn, - MEMINIT_EARLY); + link_mem_sections(nid, start_pfn, end_pfn, MEMINIT_EARLY); } return error; diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 03df20078827..01e01a530d38 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1080,9 +1080,8 @@ int __ref add_memory_resource(int nid, struct resource *res) } /* link memory sections under this node.*/ - ret = link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1), - MEMINIT_HOTPLUG); - BUG_ON(ret); + link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1), + MEMINIT_HOTPLUG); /* create new memmap entry */ if (!strcmp(res->name, "System RAM"))