s390/debug: avoid kernel warning on too large number of pages

When specifying insanely large debug buffers a kernel warning is
printed. The debug code does handle the error gracefully, though.
Instead of duplicating the check let us silence the warning to
avoid crashes when panic_on_warn is used.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

diff --git a/arch/s390/kernel/debug.c b/arch/s390/kernel/debug.c
index 6364460..263075a 100644 (file)
--- a/arch/s390/kernel/debug.c
+++ b/arch/s390/kernel/debug.c
@@ -198,9 +198,10 @@ static debug_entry_t ***debug_areas_alloc(int pages_per_area, int nr_areas)
        if (!areas)
                goto fail_malloc_areas;
        for (i = 0; i < nr_areas; i++) {
+               /* GFP_NOWARN to avoid user triggerable WARN, we handle fails */
                areas[i] = kmalloc_array(pages_per_area,
                                         sizeof(debug_entry_t *),
-                                        GFP_KERNEL);
+                                        GFP_KERNEL | __GFP_NOWARN);
                if (!areas[i])
                        goto fail_malloc_areas2;
                for (j = 0; j < pages_per_area; j++) {