From f79dbea1a1c3d4df3b224816e7f8664bbd37b679 Mon Sep 17 00:00:00 2001
From: eabdullin <eabdullin@almalinux.org>
Date: Wed, 27 May 2026 16:56:28 +0300
Subject: [PATCH] Backport patch for riscv64 architecture support

---
 config.yaml                       | 15 ++++++
 files/jitterentropy-riscv64.patch | 82 +++++++++++++++++++++++++++++++
 2 files changed, 97 insertions(+)
 create mode 100644 config.yaml
 create mode 100644 files/jitterentropy-riscv64.patch

diff --git a/config.yaml b/config.yaml
new file mode 100644
index 0000000..b5a4786
--- /dev/null
+++ b/config.yaml
@@ -0,0 +1,15 @@
+actions:
+  - modify_release:
+    - suffix: ".alma.1"
+      enabled: true
+
+  - changelog_entry:
+    - name: "Eduard Abdullin"
+      email: "eabdullin@almalinux.org"
+      line:
+        - "Backport patch for riscv64 architecture support"
+
+  - add_files:
+    - type: "patch"
+      name: "jitterentropy-riscv64.patch"
+      number: 1000
diff --git a/files/jitterentropy-riscv64.patch b/files/jitterentropy-riscv64.patch
new file mode 100644
index 0000000..cf861d9
--- /dev/null
+++ b/files/jitterentropy-riscv64.patch
@@ -0,0 +1,82 @@
+From 9671e0f658ef70bdadf18a060870f76eeb3f5f90 Mon Sep 17 00:00:00 2001
+From: Eduard Abdullin <eabdullin@cloudlinux.com>
+Date: Wed, 27 May 2026 11:48:00 +0500
+Subject: [PATCH] Backport upstream commit 59dc5997: native riscv64 timer
+
+The jitterentropy library v3.7.0 fails to build on riscv64 with -std=c11
+because none of the architecture-specific branches in
+jitterentropy-base-user.h match __riscv. Compilation falls through to
+the generic clock_gettime() path, which glibc hides behind
+_POSIX_C_SOURCE >= 199309L in C11 mode:
+
+  jitterentropy-base-user.h: In function 'jent_get_nstime':
+  jitterentropy-base-user.h:235:13: error: implicit declaration of
+    function 'clock_gettime' [-Wimplicit-function-declaration]
+  jitterentropy-base-user.h:235:27: error: 'CLOCK_REALTIME' undeclared
+
+Upstream resolved this on 2026-04-25 in commit 59dc5997 ('refactor
+architecture specific code'), which adds a native riscv branch using
+the rdtime CSR via the rdtime pseudo-instruction. That commit is a
+large refactor (17 files, +1544/-1499 lines) and has not yet appeared
+in any tagged release; the next upstream release (3.7.1) will carry it.
+
+Backport the riscv branch only, simplified for RV64. The timer
+implementation is verbatim from upstream arch/jitterentropy-arch-timer.h;
+only the structural wrapper differs (arch dispatch fused with the
+function body, as in v3.7.0). RV32 (rdtimeh/rdtime retry pair) is
+intentionally omitted because AlmaLinux only targets RV64 (riscv64).
+
+Using the native time CSR rather than clock_gettime() also preserves
+the entropy quality of the library: clock_gettime(CLOCK_REALTIME) is
+subject to NTP steering and lacks the cycle-level resolution required
+by the jitter entropy source on which all other architectures already
+rely (rdtsc on x86, cntvct_el0 on aarch64, stcke on s390x, mftb on
+ppc64le).
+
+Drop this patch when jitterentropy is rebased to >= 3.7.1.
+
+---
+ jitterentropy-base-user.h | 28 +++++++++++++++++++++++++++-
+ 1 file changed, 27 insertions(+), 1 deletion(-)
+
+diff --git jitterentropy-base-user.h jitterentropy-base-user.h
+index 0cfc526..77e3b38 100644
+--- jitterentropy-base-user.h
++++ jitterentropy-base-user.h
+@@ -203,7 +203,33 @@ static inline void jent_get_nstime(uint64_t *out)
+ 	*out = (uint64_t)__builtin_ppc_get_timebase();
+ }
+ 
+-#else /* (__x86_64__) || (__i386__) || (__aarch64__) || (__s390x__) || (__powerpc__) */
++#elif defined(__riscv)
++/*
++ * Backport of upstream commit 59dc5997 ("refactor architecture specific
++ * code", 2026-04-25) -- riscv branch only, simplified for RV64. To be
++ * obsoleted by jitterentropy >= 3.7.1, which carries the same logic in
++ * arch/jitterentropy-arch-timer.h (with full RV32 support).
++ *
++ * The "time" CSR is the platform timer and is reliably accessible from
++ * user mode on Linux (the kernel enables [s|m]counteren.TM). The "cycle"
++ * CSR has higher resolution but is not always user-readable. Override
++ * RISCV_NSTIME_INSN to switch sources, e.g. to "rdcycle".
++ *
++ * AlmaLinux only targets RV64 (riscv64); RV32 support is intentionally
++ * not backported (it would require a rdtimeh/rdtime retry pair).
++ */
++# ifndef RISCV_NSTIME_INSN
++#  define RISCV_NSTIME_INSN "rdtime"
++# endif
++
++static inline void jent_get_nstime(uint64_t *out)
++{
++	uint64_t ctr_val;
++	__asm__ __volatile__(RISCV_NSTIME_INSN " %0" : "=r" (ctr_val));
++	*out = ctr_val;
++}
++
++#else /* (__x86_64__) || (__i386__) || (__aarch64__) || (__s390x__) || (__powerpc__) || (__riscv) */
+ 
+ static inline void jent_get_nstime(uint64_t *out)
+ {
+-- 
+2.51.0