The ghes code is careful to parse and round firmware's advertised
memory requirements for CPER records, up to a maximum of 64K.
However when ghes_estatus_pool_expand() does its work, it splits
the requested size into PAGE_SIZE granules.

This means if firmware generates 5K of CPER records, and correctly
describes this in the table, __process_error() will silently fail as it
is unable to allocate more than PAGE_SIZE.

Switch the estatus pool to vmalloc() memory. On x86 vmalloc() memory
may fault and be fixed up by vmalloc_fault(). To prevent this call
vmalloc_sync_all() before an NMI handler could discover the memory.

Signed-off-by: James Morse <james.morse@arm.com>
---
 drivers/acpi/apei/ghes.c | 30 +++++++++++++++---------------
 1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index e8503c7d721f..c15264f2dc4b 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c

@@ -170,40 +170,40 @@ static int ghes_estatus_pool_init(void)
 	return 0;
 }
 
-static void ghes_estatus_pool_free_chunk_page(struct gen_pool *pool,
+static void ghes_estatus_pool_free_chunk(struct gen_pool *pool,
 					      struct gen_pool_chunk *chunk,
 					      void *data)
 {
-	free_page(chunk->start_addr);
+	vfree((void *)chunk->start_addr);
 }
 
 static void ghes_estatus_pool_exit(void)
 {
 	gen_pool_for_each_chunk(ghes_estatus_pool,
-				ghes_estatus_pool_free_chunk_page, NULL);
+				ghes_estatus_pool_free_chunk, NULL);
 	gen_pool_destroy(ghes_estatus_pool);
 }
 
 static int ghes_estatus_pool_expand(unsigned long len)
 {
-	unsigned long i, pages, size, addr;
-	int ret;
+	unsigned long size, addr;
 
 	ghes_estatus_pool_size_request += PAGE_ALIGN(len);