On 7/11/25 16:01, Peter Maydell wrote:
If the guest misprograms the PLL registers to request a zero
divisor, we currently fall over with a division by zero:
../../hw/misc/npcm_clk.c:221:14: runtime error: division by zero
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior
../../hw/misc/npcm_clk.c:221:14
Thread 1 "qemu-system-aar" received signal SIGFPE, Arithmetic exception.
0x00005555584d8f6d in npcm7xx_clk_update_pll (opaque=0x7fffed159a20) at
../../hw/misc/npcm_clk.c:221
221 freq /= PLLCON_INDV(con) * PLLCON_OTDV1(con) *
PLLCON_OTDV2(con);
Avoid this by treating this invalid setting like a stopped clock
(setting freq to 0).
Cc: [email protected]
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/549
Signed-off-by: Peter Maydell <[email protected]>
---
hw/misc/npcm_clk.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
