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sched/sem_waitirq: Swap user mappings to MMU when releasing semaphore

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sem_t is user memory and the correct mappings are needed to perform
the semaphore wait interruption.

Otherwise either a page fault, or access to the WRONG address environment
happens.
This commit is contained in:
Ville Juven 2023-03-28 13:58:31 +03:00 committed by Alan Carvalho de Assis
parent fc44cbdbdb
commit f468371332
1 changed files with 15 additions and 0 deletions
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15
sched/semaphore/sem_waitirq.c
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@ -28,6 +28,7 @@
#include <assert.h>
#include <errno.h>
#include <nuttx/addrenv.h>
#include <nuttx/irq.h>
#include <nuttx/arch.h>
@ -71,6 +72,13 @@ void nxsem_wait_irq(FAR struct tcb_s *wtcb, int errcode)
FAR struct tcb_s *rtcb = this_task();
FAR sem_t *sem = wtcb->waitobj;
#ifdef CONFIG_ARCH_ADDRENV
if (wtcb->addrenv_own)
{
addrenv_select(wtcb->addrenv_own);
}
#endif
/* It is possible that an interrupt/context switch beat us to the punch
* and already changed the task's state.
*/
@ -95,6 +103,13 @@ void nxsem_wait_irq(FAR struct tcb_s *wtcb, int errcode)
dq_rem((FAR dq_entry_t *)wtcb, SEM_WAITLIST(sem));
#ifdef CONFIG_ARCH_ADDRENV
if (wtcb->addrenv_own)
{
addrenv_restore();
}
#endif
/* Indicate that the wait is over. */
wtcb->waitobj = NULL;