Now that all locking code has been properly annotated, enable clang's
Thread Safety Analysis.
Two flags are available, -Wthread-safety, and the more recent
-Wthread-safety-pointer. The former was introduced before clang gained
RISC-V support, so it is guaranteed to be available. The latter was
introduced in clang 21, so check if the provided compiler supports it
before enabling it.
Signed-off-by: Carlos López <carlos.lopezr4096@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20260909162322.29778-16-carlos.lopezr4096@gmail.com
Signed-off-by: Anup Patel <anup@brainfault.org>
Now that the lock relationship between an event and its owner hart is
explicit, add TSA annotations for the SSE handling code. This includes
indicating which fields are protected by a spinlock, as well as
annotating which functions need to run under a spinlock.
Exclude sse_local_init(), which initializes the spinlock to be acquired,
and sse_event_get() / sse_event_put(), which perform conditional locking
that TSA is not able to follow properly.
Signed-off-by: Carlos López <carlos.lopezr4096@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20260909162322.29778-14-carlos.lopezr4096@gmail.com
Signed-off-by: Anup Patel <anup@brainfault.org>
Add Thread Safety Analysis (TSA) annotations for the HTIF driver
implementation.
This requires annotating the tohost/fromhost and htif_console_buf
globals to indicate that they are protected by htif_lock.
htif_system_reset() can be excluded since it is only called under
special circumstances from sbi_system_reset(), when all other harts
have been stopped.
Signed-off-by: Carlos López <carlos.lopezr4096@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20260909162322.29778-10-carlos.lopezr4096@gmail.com
Signed-off-by: Anup Patel <anup@brainfault.org>
Add Thread Safety Analysis (TSA) annotations for spinlock APIs, allowing
the compiler to reason about lock acquisition and release.
Annotations have a different meaning if used in header declarations vs C
file implementations. In header declarations, they specify the semantics
of the given function, meaning that we must specify that the spinlock
functions acquire and release a lock ("capability" in clang terms).
In function implementations, attributes affect the function body and
callers in the same translation unit; since the spinlock functions
contain inline assembly, they must be excluded from analysis.
Signed-off-by: Carlos López <carlos.lopezr4096@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20260909162322.29778-4-carlos.lopezr4096@gmail.com
Signed-off-by: Anup Patel <anup@brainfault.org>
pmp_get() may return an error if the given entry, given by the caller
of is_pmp_entry_mapped(), is invalid. This results in the output
parameters for pmp_get() being uninitialized. To avoid using garbage
values, check the result and return early if necessary.
This issue is not being hit because at the moment
is_pmp_entry_mapped() is only being called from a single site with a
valid hardcoded value.
Signed-off-by: Carlos López <carlos.lopezr4096@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
The fwt_hart_state struct inciludes a flexible array member, so its
allocation size will be that of the struct itself, plus that of each
of the members in the array. When calculating this size, instead of
taking the size of the struct, the size of a pointer to it was taken,
which is incorrect. Luckily, this happenned to not produce memory
corruption because the size of the non-flexible members of the struct
is the same as the size of a pointer.
Signed-off-by: Carlos López <carlos.lopezr4096@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
In several dbtr functions, we first check that the dbtr trigger is not
NULL and that its state is what we expect. However, it only makes
sense to perform the second check if the dbtr trigger is not NULL.
Othwerwise we will dereference a NULL pointer. Thus, change the
condition so that it shortcuts to the first check if necessary.
Signed-off-by: Carlos López <carlos.lopezr4096@gmail.com>
Reviewed-By: Anup Patel <anup@brainfault.org>
Carlos López