On Tue, 2015-07-21 at 18:25 +0100, Mark Brown wrote: > On Tue, Jul 21, 2015 at 02:07:25PM +0800, Henry Chen wrote: > > > Then in driver rtc-mt6397.c, it used regmap_bulk_read() to get the time > > of PMIC, and hit the null function of format_val(), because the > > regmap_bus was null. > > > It skipped the initialization of format_val() because bus == null, but > > called the format_val() at regmap_bulk_read() if bus == null. > > OK, so the issue here is that when we fall back to regmap_read() we may > do so because we have reg_read() and reg_write() functions which in turn > imply no formatting. The expectation here is that val must be an array > of int. The code doesn't completely take that into account though and > the user you're pointing at is assuming it's an array of 16 bit values > which isn't totally unreasonable if it did specify val_bits (we don't > check for that). So, could I call regmap_bulk_read() on rtc-mt6307.c, should I need to change it ? > > > Maybe it was not the good fix for this, but should be a problem need to > > be reported, or should I need to give the regmap_bus on mtk_pmic_wrap.c? > > That file isn't in mainline...
oh...it's mtk-pmic-wrap.c, sorry about that. > > memcpy() is definitely not a safe way to move from an unsigned int to a > u16 which is what your specific use case is trying to do. I'll need to > do an audit of existing users (or someone else will!) to figure out what > people are doing with .val_bits in drivers using reg_read() and > reg_write() but I think what we should be doing here is probably > providing appropriate conversion functions based on val_bits on init. Ok, got it, memcpy() should not be used here anymore. Thanks, Henry -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/