sync mm-stable with mm-hotfixes-stable to pick up depended-upon upstream changes

1 files changed, 19 insertions, 0 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d0eb280ec7e4..9c325e5e6b15 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5796,7 +5796,21 @@ static void __build_all_zonelists(void *data)
 	int nid;
 	int __maybe_unused cpu;
 	pg_data_t *self = data;
+	unsigned long flags;
 
+	/*
+	 * Explicitly disable this CPU's interrupts before taking seqlock
+	 * to prevent any IRQ handler from calling into the page allocator
+	 * (e.g. GFP_ATOMIC) that could hit zonelist_iter_begin and livelock.
+	 */
+	local_irq_save(flags);
+	/*
+	 * Explicitly disable this CPU's synchronous printk() before taking
+	 * seqlock to prevent any printk() from trying to hold port->lock, for
+	 * tty_insert_flip_string_and_push_buffer() on other CPU might be
+	 * calling kmalloc(GFP_ATOMIC | __GFP_NOWARN) with port->lock held.
+	 */
+	printk_deferred_enter();
 	write_seqlock(&zonelist_update_seq);
 
 #ifdef CONFIG_NUMA
@@ -5835,6 +5849,8 @@ static void __build_all_zonelists(void *data)
 	}
 
 	write_sequnlock(&zonelist_update_seq);
+	printk_deferred_exit();
+	local_irq_restore(flags);
 }
 
 static noinline void __init
@@ -6884,6 +6900,9 @@ static bool pfn_range_valid_contig(struct zone *z, unsigned long start_pfn,
 
 		if (PageReserved(page))
 			return false;
+
+		if (PageHuge(page))
+			return false;
 	}
 	return true;
 }