Messages in this thread | | | Subject | Re: [PATCH -next 2/4] spi: mockup: Add writeable tracepoint for spi transfer | From | "weiyongjun (A)" <> | Date | Wed, 31 Aug 2022 12:43:50 +0800 |
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On 2022/8/31 2:14, Mark Brown wrote: > On Fri, Aug 26, 2022 at 02:43:39PM +0000, Wei Yongjun wrote: > >> +#define SPI_BUFSIZ_MAX 0x1000 >> + >> +struct spi_msg_ctx { >> + int ret; >> + __u8 data[SPI_BUFSIZ_MAX]; >> +}; > > This has a hard limit on the size of messages of only 4k on the > size of messages, that seems a bit on the low side especially > considering that the example is for a flash device. There's also > things like firmware downloads which can easily exceed 4k. The > driver should at the very least report this limit via the SPI > API, and probably also complain loudly if the limit is exceeded > since it's unlikely that most drivers will actually be checking > for such a low limit given how rare they are. >
We need a limit because of BPF writeble tracepoint only support const size buffer write now. This limit can be fixed after make BPF support dynptr write.
Regards, Wei Yongjun
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