From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Date: Mon, 08 Aug 2011 16:23:09 +0400 Subject: [U-Boot] [PATCH] Fix wrong loop bound in flush_cache() when "size" is zero. In-Reply-To: <1312790868-8959-1-git-send-email-saturdaycoder@gmail.com> References: <1312790868-8959-1-git-send-email-saturdaycoder@gmail.com> Message-ID: <4E3FD52D.7090709@mvista.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hello. On 08-08-2011 12:07, Yao Cheng wrote: > The issue is found when calling flush_cache() with zero "size" argument. > The bound of loop is miscalculated in this case and flush_cache() enters a wrong flushing loop. > To fix this issue I skipped the operations when "size" is found to be zero. > Signed-off-by: Yao Cheng > Cc: Shinya Kuribayashi > --- > arch/mips/cpu/mips32/cpu.c | 5 +++++ > 1 files changed, 5 insertions(+), 0 deletions(-) > diff --git a/arch/mips/cpu/mips32/cpu.c b/arch/mips/cpu/mips32/cpu.c > index 3ae397c..1bf0094 100644 > --- a/arch/mips/cpu/mips32/cpu.c > +++ b/arch/mips/cpu/mips32/cpu.c > @@ -52,6 +52,11 @@ int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) > > void flush_cache(ulong start_addr, ulong size) > { > + /* aend will be miscalculated when size is zero, so we need return here */ > + if (size == 0) { > + return; > + } > + Please indent with tabs, not spaces. Also, doesn't this code generate warning (code before declarations)? > unsigned long lsize = CONFIG_SYS_CACHELINE_SIZE; > unsigned long addr = start_addr& ~(lsize - 1); > unsigned long aend = (start_addr + size - 1)& ~(lsize - 1); WBR, Sergei