From: David Hildenbrand <[email protected]> [ Upstream commit 5666848774ef43d3db5151ec518f1deb63515c20 ]
Let's perform all checking + offlining + removing under device_hotplug_lock, so nobody can mess with these devices via sysfs concurrently. [[email protected]: take device_hotplug_lock outside of loop] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: David Hildenbrand <[email protected]> Reviewed-by: Pavel Tatashin <[email protected]> Reviewed-by: Rashmica Gupta <[email protected]> Acked-by: Balbir Singh <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Rashmica Gupta <[email protected]> Cc: Michael Neuling <[email protected]> Cc: Boris Ostrovsky <[email protected]> Cc: Dan Williams <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Haiyang Zhang <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: John Allen <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Joonsoo Kim <[email protected]> Cc: Juergen Gross <[email protected]> Cc: Kate Stewart <[email protected]> Cc: "K. Y. Srinivasan" <[email protected]> Cc: Len Brown <[email protected]> Cc: Martin Schwidefsky <[email protected]> Cc: Mathieu Malaterre <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Nathan Fontenot <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: Philippe Ombredanne <[email protected]> Cc: Rafael J. Wysocki <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> Cc: Stephen Hemminger <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: YASUAKI ISHIMATSU <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- arch/powerpc/platforms/powernv/memtrace.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/platforms/powernv/memtrace.c b/arch/powerpc/platforms/powernv/memtrace.c index c9a6d4f3403ce..cfbd242c3e011 100644 --- a/arch/powerpc/platforms/powernv/memtrace.c +++ b/arch/powerpc/platforms/powernv/memtrace.c @@ -99,6 +99,7 @@ static int change_memblock_state(struct memory_block *mem, void *arg) return 0; } +/* called with device_hotplug_lock held */ static bool memtrace_offline_pages(u32 nid, u64 start_pfn, u64 nr_pages) { u64 end_pfn = start_pfn + nr_pages - 1; @@ -139,6 +140,7 @@ static u64 memtrace_alloc_node(u32 nid, u64 size) /* Trace memory needs to be aligned to the size */ end_pfn = round_down(end_pfn - nr_pages, nr_pages); + lock_device_hotplug(); for (base_pfn = end_pfn; base_pfn > start_pfn; base_pfn -= nr_pages) { if (memtrace_offline_pages(nid, base_pfn, nr_pages) == true) { /* @@ -147,7 +149,6 @@ static u64 memtrace_alloc_node(u32 nid, u64 size) * we never try to remove memory that spans two iomem * resources. */ - lock_device_hotplug(); end_pfn = base_pfn + nr_pages; for (pfn = base_pfn; pfn < end_pfn; pfn += bytes>> PAGE_SHIFT) { remove_memory(nid, pfn << PAGE_SHIFT, bytes); @@ -156,6 +157,7 @@ static u64 memtrace_alloc_node(u32 nid, u64 size) return base_pfn << PAGE_SHIFT; } } + unlock_device_hotplug(); return 0; } -- 2.20.1
