On 7/9/20 4:15 PM, Peter Maydell wrote: > On Thu, 9 Jul 2020 at 14:56, Philippe Mathieu-Daudé <f4...@amsat.org> wrote: >> >> On 7/7/20 10:29 PM, Niek Linnenbank wrote: >>> So I manually copy & pasted the change into hw/sd/sd.c to test it. >>> It looks like the check works, but my concern is that with this change, >>> we will be getting this error on 'off-the-shelf' images as well. >>> For example, the latest Raspbian image size also isn't a power of two: >>> >>> $ ./arm-softmmu/qemu-system-arm -M raspi2 -sd >>> ~/Downloads/2020-05-27-raspios-buster-lite-armhf.img -nographic >>> WARNING: Image format was not specified for >>> '/home/me/Downloads/2020-05-27-raspios-buster-lite-armhf.img' and >>> probing guessed raw. >>> Automatically detecting the format is dangerous for raw images, >>> write operations on block 0 will be restricted. >>> Specify the 'raw' format explicitly to remove the restrictions. >>> qemu-system-arm: Invalid SD card size: 1.73 GiB (expecting at least 2 GiB) >>> >>> If we do decide that the change is needed, I would like to propose that >>> we also give the user some instructions >>> on how to fix it, maybe some 'dd' command? >> >> On POSIX we can suggest to use 'truncate -s 2G' from coreutils. >> This is not in the default Darwin packages. >> On Windows I have no clue. > > dd/truncate etc won't work if the image file is not raw (eg if > it's qcow2).
Good catch... > The only chance you have of something that's actually > generic would probably involve "qemu-img resize". But I'm a bit > wary of having an error message that recommends that, because > what if we got it wrong? I am not sure what to recommend then. Would that work as hint? qemu-system-arm -M raspi2 -sd ./buster-lite-armhf.img qemu-system-arm: Invalid SD card size: 1.73 GiB SD card size has to be a power of 2, e.g. 2GiB.
