nvram_clear_error_log() calls ppc_md.nvram_write() even when nvram_error_log_index is -1 (invalid). The nvram_write() function does not check for a negative offset. Check nvram_error_log_index as the other nvram log functions do. Signed-off-by: Thomas Gleixner Cc: Benjamin Herrenschmidt Cc: linuxppc-dev@ozlabs.org --- arch/powerpc/kernel/nvram_64.c | 3 +++ 1 file changed, 3 insertions(+) Index: linux-2.6-tip/arch/powerpc/kernel/nvram_64.c =================================================================== --- linux-2.6-tip.orig/arch/powerpc/kernel/nvram_64.c +++ linux-2.6-tip/arch/powerpc/kernel/nvram_64.c @@ -681,6 +681,9 @@ int nvram_clear_error_log(void) int clear_word = ERR_FLAG_ALREADY_LOGGED; int rc; + if (nvram_error_log_index == -1) + return -1; + tmp_index = nvram_error_log_index; rc = ppc_md.nvram_write((char *)&clear_word, sizeof(int), &tmp_index);