das problem scheint verbreiteter zu sein:

https://github.com/espressif/esptool...ment-913865576

aber das hier ist doch verrückt, oder?
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Spent a week with this issue before finding a solution.
I'm using Ubuntu 20.04, kernel 5.11.0-37-generic
I rebuilt the kernel and copied the ch341.ko driver to my system
Note: read all of the following before starting.
the following site shows how to rebuild a Kernel for Ubuntu
https://wiki.ubuntu.com/Kernel/BuildYourOwnKernel
When the Wiki indicates to add 'deb-src' paths to your sources.list file (don't)
make a copy of the original sources.list file, then edit the sources.list file and
replace the beginning of each '# deb-src' line with 'deb-src', basically remove the '# ' on each of those lines
after saving the file, do a 'sudo apt update'
/etc/apt/sources.list
after getting the source using,
apt-get source linux-image-unsigned-$(uname -r)
ya have to delete this line ".bulk_in_size = 512," from the ch341.c file
ubuntu-kernel/linux-hwe-5.11-5.11.0/drivers/usb/serial/ch341.c
then build the kernel per the above Wiki site
do not install the .deb file per the wiki, only copy the ch341.ko file
The location of the ch341.ko driver is
ubuntu-kernel/linux-hwe-5.11-5.11.0/debian/build/build-generic/drivers/usb/serial/ch341.ko
the location of ch341.ko on your system should be at
/lib/modules/5.11.0-37-generic/kernel/drivers/usb/serial/ch341.ko
rename the ch341.ko driver before copying your new driver there.
the '5.11.0-37-generic' will be what ever 'uname -r' returns.
reboot your system, ya should be good to go.
Hope this helps
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