| Message ID | 20231114180238.1522782-3-sumanthk@linux.ibm.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | implement "memmap on memory" feature on s390 | expand |
On 14.11.23 19:02, Sumanth Korikkar wrote: > In add_memory_resource(), creation of memory block devices occurs after > successful call to arch_add_memory(). However, creation of memory block > devices could fail. In that case, arch_remove_memory() is called to > perform necessary cleanup. > > Currently with or without altmap support, arch_remove_memory() is always > passed with altmap set to NULL during error handling. This leads to > freeing of struct pages using free_pages(), eventhough the allocation > might have been performed with altmap support via > altmap_alloc_block_buf(). > > Fix the error handling by passing altmap in arch_remove_memory(). This > ensures the following: > * When altmap is disabled, deallocation of the struct pages array occurs > via free_pages(). > * When altmap is enabled, deallocation occurs via vmem_altmap_free(). > > Fixes: db051a0dac13 ("mm/memory_hotplug: create memory block devices after arch_add_memory()") That's the wrong commit. We didn't support memmap-on-memory back then. Likely it should be: Fixes: a08a2ae34613 ("mm,memory_hotplug: allocate memmap from the added memory range") > Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com> > Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com> > --- > mm/memory_hotplug.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index c8238fc5edcb..4f476a970e84 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -1458,7 +1458,7 @@ int __ref add_memory_resource(int nid, struct resource *res, mhp_t mhp_flags) > /* create memory block devices after memory was added */ > ret = create_memory_block_devices(start, size, params.altmap, group); > if (ret) { > - arch_remove_memory(start, size, NULL); > + arch_remove_memory(start, size, params.altmap); > goto error_free; > } > Indeed; this will conflict with Vishals patches, ccing him.
On Tue, Nov 14, 2023 at 07:36:20PM +0100, David Hildenbrand wrote: > On 14.11.23 19:02, Sumanth Korikkar wrote: > > In add_memory_resource(), creation of memory block devices occurs after > > successful call to arch_add_memory(). However, creation of memory block > > devices could fail. In that case, arch_remove_memory() is called to > > perform necessary cleanup. > > > > Currently with or without altmap support, arch_remove_memory() is always > > passed with altmap set to NULL during error handling. This leads to > > freeing of struct pages using free_pages(), eventhough the allocation > > might have been performed with altmap support via > > altmap_alloc_block_buf(). > > > > Fix the error handling by passing altmap in arch_remove_memory(). This > > ensures the following: > > * When altmap is disabled, deallocation of the struct pages array occurs > > via free_pages(). > > * When altmap is enabled, deallocation occurs via vmem_altmap_free(). > > > > Fixes: db051a0dac13 ("mm/memory_hotplug: create memory block devices after arch_add_memory()") > > That's the wrong commit. We didn't support memmap-on-memory back then. > > Likely it should be: > > Fixes: a08a2ae34613 ("mm,memory_hotplug: allocate memmap from the added > memory range") > Ok, I will change it accordingly Thanks ... > > Indeed; this will conflict with Vishals patches, ccing him. > > -- > Cheers, > > David / dhildenb >
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index c8238fc5edcb..4f476a970e84 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1458,7 +1458,7 @@ int __ref add_memory_resource(int nid, struct resource *res, mhp_t mhp_flags) /* create memory block devices after memory was added */ ret = create_memory_block_devices(start, size, params.altmap, group); if (ret) { - arch_remove_memory(start, size, NULL); + arch_remove_memory(start, size, params.altmap); goto error_free; }
In add_memory_resource(), creation of memory block devices occurs after successful call to arch_add_memory(). However, creation of memory block devices could fail. In that case, arch_remove_memory() is called to perform necessary cleanup. Currently with or without altmap support, arch_remove_memory() is always passed with altmap set to NULL during error handling. This leads to freeing of struct pages using free_pages(), eventhough the allocation might have been performed with altmap support via altmap_alloc_block_buf(). Fix the error handling by passing altmap in arch_remove_memory(). This ensures the following: * When altmap is disabled, deallocation of the struct pages array occurs via free_pages(). * When altmap is enabled, deallocation occurs via vmem_altmap_free(). Fixes: db051a0dac13 ("mm/memory_hotplug: create memory block devices after arch_add_memory()") Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com> --- mm/memory_hotplug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)