Yidi Lin 8610dd5022 libpayload: usbmsc: Prevent usbdisk_remove() from being called twice
When removing SD card from USB card reader, the USB MSC stack does
not detach the device immediately. Instead, the USB MSC stack calls
usbdisk_remove() and calls usb_msc_destroy() after several pollings.
It results in usbdisk_remove() being called twice.

Since the usbmsc_inst_t instance is freed after first usbdisk_remove()
call, the second call invokes an invalid usbmsc_inst_t instance and
causes exception in CPU.

This patch prevents usbdisk_remove() from being called twice by setting
usbdisk_created to zero.

BUG=b:239492347
TEST=insert an empty SD card into the USB card reader then remove
     the SD card. AP firmware does not crash.

Change-Id: I0675e9fde3e770d63dd0047928356a204245ef18
Signed-off-by: Yidi Lin <yidilin@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/66449
Reviewed-by: Yu-Ping Wu <yupingso@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2022-08-12 17:14:54 +00:00
..
2022-07-04 14:02:26 +00:00
2022-06-07 12:34:35 +00:00
2022-07-04 14:02:26 +00:00
2020-03-02 15:03:03 +00:00
2021-10-11 12:59:57 +00:00

-------------------------------------------------------------------------------
libpayload README
-------------------------------------------------------------------------------

libpayload is a minimal library to support standalone payloads
that can be booted with firmware like coreboot. It handles the setup
code, and provides common C library symbols such as malloc() and printf().

Note: This is _not_ a standard library for use with an operating system,
rather it's only useful for coreboot payload development!
See https://www.coreboot.org for details on coreboot.


Installation
------------

 $ git clone https://review.coreboot.org/coreboot.git

 $ cd coreboot/payloads/libpayload

 $ make menuconfig

 $ make

 $ make install (optional, will install into ./install per default)

On x86 systems, libpayload will always be 32-bit even if your host OS runs
in 64-bit, so you might have to install the 32-bit libgcc version.
On Debian systems you'd do 'apt-get install gcc-multilib' for example.

Run 'make distclean' before switching boards. This command will remove
your current .config file, so you need 'make menuconfig' again or
'make defconfig' in order to set up configuration. Default configuration
is based on 'configs/defconfig'. See the configs/ directory for examples
of configuration.


Usage
-----

Here's an example of a very simple payload (hello.c) and how to build it:

 #include <libpayload.h>

 int main(void)
 {
     printf("Hello, world!\n");
     return 0;
 }

Building the payload using the 'lpgcc' compiler wrapper:

 $ lpgcc -o hello.elf hello.c

Please see the sample/ directory for details.


Website and Mailing List
------------------------

The main website is https://www.coreboot.org/Libpayload.

For additional information, patches, and discussions, please join the
coreboot mailing list at https://www.coreboot.org/Mailinglist, where most
libpayload developers are subscribed.


Copyright and License
---------------------

See LICENSES.