diff --git a/redox-rt/src/signal.rs b/redox-rt/src/signal.rs
index b29f9218e7..628e08c53b 100644
--- a/redox-rt/src/signal.rs
+++ b/redox-rt/src/signal.rs
@@ -351,11 +351,12 @@ fn modify_sigmask(old: Option<&mut u64>, op: Option<impl FnOnce(u64) -> u64>) ->
 
     let next = !op(!prev);
 
-    let pending = set_allowset_raw(&ctl.word, prev, next);
+    let thread_pending = set_allowset_raw(&ctl.word, prev, next);
+    let proc_pending = PROC_CONTROL_STRUCT.pending.load(Ordering::Relaxed);
 
     // POSIX requires that at least one pending unblocked signal be delivered before
     // pthread_sigmask returns, if there is one.
-    if pending != 0 {
+    if (thread_pending | proc_pending) & next != 0 {
         unsafe {
             manually_enter_trampoline();
         }
diff --git a/src/header/signal/mod.rs b/src/header/signal/mod.rs
index db7d03da24..e0309b90c0 100644
--- a/src/header/signal/mod.rs
+++ b/src/header/signal/mod.rs
@@ -387,9 +387,13 @@ pub unsafe extern "C" fn sigpending(set: *mut sigset_t) -> c_int {
         .or_minus_one_errno()
 }
 
-const BELOW_SIGRTMIN_MASK: sigset_t = (1 << SIGRTMIN) - 1;
-const STANDARD_SIG_MASK: sigset_t = (1 << 32) - 1;
-const RLCT_SIGNAL_MASK: sigset_t = BELOW_SIGRTMIN_MASK & !STANDARD_SIG_MASK;
+// TODO: Double-check this mask.
+// This prevents the application from blocking the two signals SIGRTMIN - 1 and SIGRTMIN - 2 which
+// are (at least meant to be) used internally for timers and pthread cancellation. On Linux this is
+// 32 and 33 (same as NPTL reserves), whereas this on Redox is 33 and 34 (TODO: could this be
+// changed to 32 and 33 for Redox too, since there's currently no support for "sigqueue" targeting
+// specific threads).
+const RLCT_SIGNAL_MASK: sigset_t = (1 << ((SIGRTMIN - 1) - 1)) | (1 << (SIGRTMIN - 2) - 1);
 
 /// See <https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigprocmask.html>.
 #[unsafe(no_mangle)]
diff --git a/src/platform/redox/signal.rs b/src/platform/redox/signal.rs
index 8010d37b92..f25b188a0e 100644
--- a/src/platform/redox/signal.rs
+++ b/src/platform/redox/signal.rs
@@ -7,8 +7,8 @@ use crate::{
     header::{
         errno::{EINVAL, ENOSYS},
         signal::{
-            NSIG, SA_SIGINFO, SIG_BLOCK, SIG_DFL, SIG_IGN, SIG_SETMASK, SIG_UNBLOCK, SIGRTMIN,
-            SS_DISABLE, SS_ONSTACK, sigaction, siginfo_t, sigset_t, sigval, stack_t, ucontext_t,
+            NSIG, SA_SIGINFO, SIG_BLOCK, SIG_DFL, SIG_IGN, SIG_SETMASK, SIG_UNBLOCK, SS_DISABLE,
+            SS_ONSTACK, sigaction, siginfo_t, sigset_t, sigval, stack_t, ucontext_t,
         },
         sys_time::{ITIMER_REAL, itimerval},
         time::timespec,
@@ -86,18 +86,6 @@ impl PalSignal for Sys {
 
     fn raise(sig: c_int) -> Result<()> {
         // TODO: Bypass kernel?
-        const n_sig: c_int = NSIG as c_int;
-        const rt_min: c_int = SIGRTMIN as c_int;
-        const rt_max: c_int = SIGRTMIN as c_int;
-
-        match sig {
-            0..n_sig => {}
-            rt_min..=rt_max => {}
-            _ => {
-                return Err(Errno(EINVAL));
-            }
-        }
-
         unsafe { Self::rlct_kill(Self::current_os_tid(), sig as _) }
     }