hujun5 0e1b432dd0 armv7/8m: fix regresion from https://github.com/apache/nuttx/pull/14881 ... reason: svc call may trigger hardfault Background The origin of this issue is our desire to eliminate the function of storing "regs" in g_current_regs and instead utilize (*running_task)->xcp.regs for storage. The benefits of this approach include faster storage speed and avoiding multiple accesses to g_current_regs during context switching, thus ensuring that whether returning from an interrupt or an exception, we consistently use this_task()->xcp.regs Issue Encountered However, when storing registers, we must ensure that (running_task)->xcp.regs is invalid so that it can be safely overwritten. According to the existing logic, the only scenario where (running_task)->xcp.regs is valid is during restore_context. We must accurately identify this scenario. Initially, we used the condition (running_task)==NULL for this purpose, but we deemed this approach unsatisfactory as it did not align well with the actual logic. (running_task) should not be NULL. Consequently, we adopted other arch-specific methods for judgment, but due to special logic in some arch, the judgment was not accurate, leading to this issue. Solution: For armv6-m, we haven't found a more suitable solution, so we are sticking with (*running_task)==NULL. For armv7-m/armv8-m, by removing support for primask, we can achieve accurate judgment. PRIMASK is a design in armv6-m, that's why arm introduce BASEPRI from armv7-m. It's wrong to provide this option for armv7-m/armv8-m arch. Signed-off-by: hujun5 <hujun5@xiaomi.com>		2024-12-09 12:20:13 +08:00
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defconfig	armv7/8m: fix regresion from https://github.com/apache/nuttx/pull/14881	2024-12-09 12:20:13 +08:00