[system]: Made longjmp save for context switch

* Patched longjmp to be context-switch safe
  longjmp modifies the windowbase and windowstart
  registers, which isn't safe if a context switch
  occurs during the modification. After a context
  switch, windowstart and windowbase will be
  different, leading to a wrongly set windowstart
  bit due to longjmp writing it based on the
  windowbase before the context switch. This
  corrupts the registers at the next window
  overflow reaching that wrongly set bit.

  The solution is to disable interrupts during
  this code. It is only 6 instructions long,
  the impact shouldn't be significant.

  The fix is implemented as a wrapper which
  replaces the original first instructions of
  longjmp which are buggy. Then, it jumps back
  to execute the rest of the original longjmp
  function.

  Added a comparably reliable test to the
  test apps.
This commit is contained in:
Jakob Hasse
2021-04-08 12:16:17 +08:00
committed by bot
parent 88b3e0d8d8
commit aabdb2c7a1
14 changed files with 272 additions and 1 deletions
@@ -32,4 +32,6 @@ CFLAGS += -D BOOTLOADER_BUILD=1
# include the top-level "project" include directory, for sdkconfig.h
CFLAGS += -I$(BUILD_DIR_BASE)/../include
COMPONENT_ADD_LDFLAGS += -l$(COMPONENT_NAME) -Wl,--wrap=longjmp \
include $(IDF_PATH)/make/project.mk