* [PATCH v4 0/3] riscv32 library enhancements and build fixes
@ 2026-04-14 10:26 Dmitry Antipov
2026-04-14 10:26 ` [PATCH v4 1/3] riscv: add platform-specific double word shifts for riscv32 Dmitry Antipov
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Dmitry Antipov @ 2026-04-14 10:26 UTC (permalink / raw)
To: Andrew Morton
Cc: Andy Shevchenko, Charlie Jenkins, Paul Walmsley, Palmer Dabbelt,
Albert Ou, Ard Biesheuvel, linux-riscv, linux-efi, Dmitry Antipov
This series should immediately follow v8 of lib and lib/cmdline enhancements,
see https://patchew.org/linux/20260212164413.889625-1-dmantipov@yandex.ru.
Started from riscv32 build quirk, now it aims to provide platform-specific
double-word shifts and corresponding KUnit test (tested on ARM as well).
Dmitry Antipov (3):
riscv: add platform-specific double word shifts for riscv32
lib: kunit: add tests for __ashldi3(), __ashrdi3(), and __lshrdi3()
riscv: fix building compressed EFI image
arch/riscv/Kconfig | 3 -
arch/riscv/kernel/image-vars.h | 7 ++
arch/riscv/lib/Makefile | 1 +
arch/riscv/lib/ashldi3.S | 36 ++++++
arch/riscv/lib/ashrdi3.S | 37 ++++++
arch/riscv/lib/lshrdi3.S | 36 ++++++
drivers/firmware/efi/Kconfig | 4 +
drivers/firmware/efi/libstub/Makefile | 3 +-
lib/Kconfig.debug | 10 ++
lib/tests/Makefile | 1 +
lib/tests/shdi3_kunit.c | 175 ++++++++++++++++++++++++++
11 files changed, 309 insertions(+), 4 deletions(-)
create mode 100644 arch/riscv/lib/ashldi3.S
create mode 100644 arch/riscv/lib/ashrdi3.S
create mode 100644 arch/riscv/lib/lshrdi3.S
create mode 100644 lib/tests/shdi3_kunit.c
--
2.53.0
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v4 1/3] riscv: add platform-specific double word shifts for riscv32
2026-04-14 10:26 [PATCH v4 0/3] riscv32 library enhancements and build fixes Dmitry Antipov
@ 2026-04-14 10:26 ` Dmitry Antipov
2026-04-14 10:26 ` [PATCH v4 2/3] lib: kunit: add tests for __ashldi3(), __ashrdi3(), and __lshrdi3() Dmitry Antipov
2026-04-14 10:26 ` [PATCH v4 3/3] riscv: fix building compressed EFI image Dmitry Antipov
2 siblings, 0 replies; 6+ messages in thread
From: Dmitry Antipov @ 2026-04-14 10:26 UTC (permalink / raw)
To: Andrew Morton
Cc: Andy Shevchenko, Charlie Jenkins, Paul Walmsley, Palmer Dabbelt,
Albert Ou, Ard Biesheuvel, linux-riscv, linux-efi, Dmitry Antipov,
kernel test robot
Add riscv32-specific '__ashldi3()', '__ashrdi3()', and '__lshrdi3()'.
Initially it was intended to fix the following link error observed
when building EFI-enabled kernel with CONFIG_EFI_STUB=y and
CONFIG_EFI_GENERIC_STUB=y:
riscv32-linux-gnu-ld: ./drivers/firmware/efi/libstub/lib-cmdline.stub.o: in function `__efistub_.L49':
__efistub_cmdline.c:(.init.text+0x1f2): undefined reference to `__efistub___ashldi3'
riscv32-linux-gnu-ld: __efistub_cmdline.c:(.init.text+0x202): undefined reference to `__efistub___lshrdi3'
Reported at [1] trying to build https://patchew.org/linux/20260212164413.889625-1-dmantipov@yandex.ru,
tested with 'qemu-system-riscv32 -M virt' only.
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202603041925.KLKqpK6N-lkp@intel.com [1]
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Charlie Jenkins <thecharlesjenkins@gmail.com>
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
---
v4: bump version to match the series
v3: more tests by Charlie Jenkins
v2: adjust commit message
---
arch/riscv/Kconfig | 3 ---
arch/riscv/kernel/image-vars.h | 7 +++++++
arch/riscv/lib/Makefile | 1 +
arch/riscv/lib/ashldi3.S | 36 +++++++++++++++++++++++++++++++++
arch/riscv/lib/ashrdi3.S | 37 ++++++++++++++++++++++++++++++++++
arch/riscv/lib/lshrdi3.S | 36 +++++++++++++++++++++++++++++++++
6 files changed, 117 insertions(+), 3 deletions(-)
create mode 100644 arch/riscv/lib/ashldi3.S
create mode 100644 arch/riscv/lib/ashrdi3.S
create mode 100644 arch/riscv/lib/lshrdi3.S
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index ddc534402400d..14b838d408b8c 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -404,9 +404,6 @@ config ARCH_RV32I
bool "RV32I"
depends on NONPORTABLE
select 32BIT
- select GENERIC_LIB_ASHLDI3
- select GENERIC_LIB_ASHRDI3
- select GENERIC_LIB_LSHRDI3
select GENERIC_LIB_UCMPDI2
config ARCH_RV64I
diff --git a/arch/riscv/kernel/image-vars.h b/arch/riscv/kernel/image-vars.h
index 3bd9d06a8b8ff..d66e06daf13eb 100644
--- a/arch/riscv/kernel/image-vars.h
+++ b/arch/riscv/kernel/image-vars.h
@@ -32,6 +32,13 @@ __efistub___init_text_end = __init_text_end;
__efistub_sysfb_primary_display = sysfb_primary_display;
#endif
+/*
+ * These double-word integer shifts are used
+ * by the library code and so EFI stub as well.
+ */
+PROVIDE(__efistub___lshrdi3 = __lshrdi3);
+PROVIDE(__efistub___ashldi3 = __ashldi3);
+
#endif
#endif /* __RISCV_KERNEL_IMAGE_VARS_H */
diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile
index bbc031124974e..7cee3da80c682 100644
--- a/arch/riscv/lib/Makefile
+++ b/arch/riscv/lib/Makefile
@@ -13,6 +13,7 @@ ifeq ($(CONFIG_MMU), y)
lib-$(CONFIG_RISCV_ISA_V) += uaccess_vector.o
endif
lib-$(CONFIG_MMU) += uaccess.o
+lib-$(CONFIG_32BIT) += ashldi3.o ashrdi3.o lshrdi3.o
lib-$(CONFIG_64BIT) += tishift.o
lib-$(CONFIG_RISCV_ISA_ZICBOZ) += clear_page.o
obj-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o
diff --git a/arch/riscv/lib/ashldi3.S b/arch/riscv/lib/ashldi3.S
new file mode 100644
index 0000000000000..c3408862e2f6a
--- /dev/null
+++ b/arch/riscv/lib/ashldi3.S
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/**
+ * Adopted for the Linux kernel from IPXE project, see
+ * https://github.com/ipxe/ipxe/blob/master/src/arch/riscv32/libgcc/llshift.S
+ */
+
+#include <linux/linkage.h>
+#include <asm/asm.h>
+
+/**
+ * Shift left
+ *
+ * @v a1:a0 Value to shift
+ * @v a2 Shift amount
+ * @ret a1:a0 Shifted value
+ */
+
+SYM_FUNC_START(__ashldi3)
+
+ /* Perform shift by 32 bits, if applicable */
+ li t0, 32
+ sub t1, t0, a2
+ bgtz t1, 1f
+ mv a1, a0
+ mv a0, zero
+1: /* Perform shift by modulo-32 bits, if applicable */
+ andi a2, a2, 0x1f
+ beqz a2, 2f
+ srl t2, a0, t1
+ sll a0, a0, a2
+ sll a1, a1, a2
+ or a1, a1, t2
+2: ret
+
+SYM_FUNC_END(__ashldi3)
+EXPORT_SYMBOL(__ashldi3)
diff --git a/arch/riscv/lib/ashrdi3.S b/arch/riscv/lib/ashrdi3.S
new file mode 100644
index 0000000000000..dd42b3cbb173a
--- /dev/null
+++ b/arch/riscv/lib/ashrdi3.S
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/**
+ * Adopted for the Linux kernel from IPXE project, see
+ * https://github.com/ipxe/ipxe/blob/master/src/arch/riscv32/libgcc/llshift.S
+ */
+
+#include <linux/linkage.h>
+#include <asm/asm.h>
+
+/**
+ * Arithmetic shift right
+ *
+ * @v a1:a0 Value to shift
+ * @v a2 Shift amount
+ * @ret a1:a0 Shifted value
+ */
+
+SYM_FUNC_START(__ashrdi3)
+
+ /* Perform shift by 32 bits, if applicable */
+ li t0, 32
+ sub t1, t0, a2
+ bgtz t1, 1f
+ mv a0, a1
+ srai a1, a1, 16
+ srai a1, a1, 16
+1: /* Perform shift by modulo-32 bits, if applicable */
+ andi a2, a2, 0x1f
+ beqz a2, 2f
+ sll t2, a1, t1
+ sra a1, a1, a2
+ srl a0, a0, a2
+ or a0, a0, t2
+2: ret
+
+SYM_FUNC_END(__ashrdi3)
+EXPORT_SYMBOL(__ashrdi3)
diff --git a/arch/riscv/lib/lshrdi3.S b/arch/riscv/lib/lshrdi3.S
new file mode 100644
index 0000000000000..1af03985ccb72
--- /dev/null
+++ b/arch/riscv/lib/lshrdi3.S
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/**
+ * Adopted for the Linux kernel from IPXE project, see
+ * https://github.com/ipxe/ipxe/blob/master/src/arch/riscv32/libgcc/llshift.S
+ */
+
+#include <linux/linkage.h>
+#include <asm/asm.h>
+
+/**
+ * Logical shift right
+ *
+ * @v a1:a0 Value to shift
+ * @v a2 Shift amount
+ * @ret a1:a0 Shifted value
+ */
+
+SYM_FUNC_START(__lshrdi3)
+
+ /* Perform shift by 32 bits, if applicable */
+ li t0, 32
+ sub t1, t0, a2
+ bgtz t1, 1f
+ mv a0, a1
+ mv a1, zero
+1: /* Perform shift by modulo-32 bits, if applicable */
+ andi a2, a2, 0x1f
+ beqz a2, 2f
+ sll t2, a1, t1
+ srl a1, a1, a2
+ srl a0, a0, a2
+ or a0, a0, t2
+2: ret
+
+SYM_FUNC_END(__lshrdi3)
+EXPORT_SYMBOL(__lshrdi3)
--
2.53.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v4 2/3] lib: kunit: add tests for __ashldi3(), __ashrdi3(), and __lshrdi3()
2026-04-14 10:26 [PATCH v4 0/3] riscv32 library enhancements and build fixes Dmitry Antipov
2026-04-14 10:26 ` [PATCH v4 1/3] riscv: add platform-specific double word shifts for riscv32 Dmitry Antipov
@ 2026-04-14 10:26 ` Dmitry Antipov
2026-04-14 10:26 ` [PATCH v4 3/3] riscv: fix building compressed EFI image Dmitry Antipov
2 siblings, 0 replies; 6+ messages in thread
From: Dmitry Antipov @ 2026-04-14 10:26 UTC (permalink / raw)
To: Andrew Morton
Cc: Andy Shevchenko, Charlie Jenkins, Paul Walmsley, Palmer Dabbelt,
Albert Ou, Ard Biesheuvel, linux-riscv, linux-efi, Dmitry Antipov
Add KUnit tests for '__ashldi3()', '__ashrdi3()', and '__lshrdi3()'
helper functions used to implement 64-bit arithmetic shift left,
arithmetic shift right and logical shift right, respectively,
on a 32-bit CPUs.
Tested with 'qemu-system-riscv32 -M virt' and 'qemu-system-arm -M virt'.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Tested-by: Charlie Jenkins <thecharlesjenkins@gmail.com>
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
---
v4: bump version to match the series
v3: more tests by Charlie Jenkins
v2: include test-specific headers rather than generic linux/kernel.h
---
lib/Kconfig.debug | 10 +++
lib/tests/Makefile | 1 +
lib/tests/shdi3_kunit.c | 175 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 186 insertions(+)
create mode 100644 lib/tests/shdi3_kunit.c
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 94eb2667b7e13..635c5f1c3d4ea 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2942,6 +2942,16 @@ config BITS_TEST
If unsure, say N.
+config SHDI3_KUNIT_TEST
+ tristate "KUnit test for __ashldi3(), __ashrdi3(), and __lshrdi3()"
+ depends on KUNIT
+ depends on (32BIT || ARM)
+ help
+ This builds the unit test for __ashldi3(), __ashrdi3(), and
+ __lshrdi3() helper functions used to implement 64-bit arithmetic
+ shift left, arithmetic shift right and logical shift right,
+ respectively, on a 32-bit CPUs.
+
config SLUB_KUNIT_TEST
tristate "KUnit test for SLUB cache error detection" if !KUNIT_ALL_TESTS
depends on SLUB_DEBUG && KUNIT
diff --git a/lib/tests/Makefile b/lib/tests/Makefile
index 05f74edbc62bf..db678ccdd8b15 100644
--- a/lib/tests/Makefile
+++ b/lib/tests/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_BASE64_KUNIT) += base64_kunit.o
obj-$(CONFIG_BITOPS_KUNIT) += bitops_kunit.o
obj-$(CONFIG_BITFIELD_KUNIT) += bitfield_kunit.o
obj-$(CONFIG_BITS_TEST) += test_bits.o
+obj-$(CONFIG_SHDI3_KUNIT_TEST) += shdi3_kunit.o
obj-$(CONFIG_BLACKHOLE_DEV_KUNIT_TEST) += blackhole_dev_kunit.o
obj-$(CONFIG_CHECKSUM_KUNIT) += checksum_kunit.o
obj-$(CONFIG_CMDLINE_KUNIT_TEST) += cmdline_kunit.o
diff --git a/lib/tests/shdi3_kunit.c b/lib/tests/shdi3_kunit.c
new file mode 100644
index 0000000000000..44f65e66512b5
--- /dev/null
+++ b/lib/tests/shdi3_kunit.c
@@ -0,0 +1,175 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR Apache-2.0
+/*
+ * Test cases for __ashldi3(), __ashrdi3(), and __lshrdi3().
+ */
+
+#include <linux/array_size.h>
+#include <linux/module.h>
+#include <linux/libgcc.h>
+#include <kunit/test.h>
+
+struct shdi3_test_entry {
+ long long input;
+ int shift;
+ long long result;
+};
+
+static const struct shdi3_test_entry ashldi3_testdata[] = {
+ /* https://github.com/llvm/llvm-project/compiler-rt/test/builtins/Unit/ashldi3_test.c */
+ { 0x0123456789ABCDEFLL, 0, 0x123456789ABCDEFLL },
+ { 0x0123456789ABCDEFLL, 1, 0x2468ACF13579BDELL },
+ { 0x0123456789ABCDEFLL, 2, 0x48D159E26AF37BCLL },
+ { 0x0123456789ABCDEFLL, 3, 0x91A2B3C4D5E6F78LL },
+ { 0x0123456789ABCDEFLL, 4, 0x123456789ABCDEF0LL },
+ { 0x0123456789ABCDEFLL, 28, 0x789ABCDEF0000000LL },
+ { 0x0123456789ABCDEFLL, 29, 0xF13579BDE0000000LL },
+ { 0x0123456789ABCDEFLL, 30, 0xE26AF37BC0000000LL },
+ { 0x0123456789ABCDEFLL, 31, 0xC4D5E6F780000000LL },
+ { 0x0123456789ABCDEFLL, 32, 0x89ABCDEF00000000LL },
+ { 0x0123456789ABCDEFLL, 33, 0x13579BDE00000000LL },
+ { 0x0123456789ABCDEFLL, 34, 0x26AF37BC00000000LL },
+ { 0x0123456789ABCDEFLL, 35, 0x4D5E6F7800000000LL },
+ { 0x0123456789ABCDEFLL, 36, 0x9ABCDEF000000000LL },
+ { 0x0123456789ABCDEFLL, 60, 0xF000000000000000LL },
+ { 0x0123456789ABCDEFLL, 61, 0xE000000000000000LL },
+ { 0x0123456789ABCDEFLL, 62, 0xC000000000000000LL },
+ { 0x0123456789ABCDEFLL, 63, 0x8000000000000000LL },
+};
+
+static void shdi3_test_ashldi3(struct kunit *test)
+{
+ const struct shdi3_test_entry *e;
+ long long ret;
+
+ for (e = ashldi3_testdata;
+ e < ashldi3_testdata + ARRAY_SIZE(ashldi3_testdata); e++) {
+ ret = __ashldi3(e->input, e->shift);
+ KUNIT_EXPECT_EQ_MSG(test, ret, e->result,
+ " when evaluating __ashldi3(%lld, %d)",
+ e->input, e->shift);
+ }
+}
+
+static const struct shdi3_test_entry ashrdi3_testdata[] = {
+ /* https://github.com/llvm/llvm-project/compiler-rt/test/builtins/Unit/ashrdi3_test.c */
+ { 0x0123456789ABCDEFLL, 0, 0x123456789ABCDEFLL },
+ { 0x0123456789ABCDEFLL, 1, 0x91A2B3C4D5E6F7LL },
+ { 0x0123456789ABCDEFLL, 2, 0x48D159E26AF37BLL },
+ { 0x0123456789ABCDEFLL, 3, 0x2468ACF13579BDLL },
+ { 0x0123456789ABCDEFLL, 4, 0x123456789ABCDELL },
+ { 0x0123456789ABCDEFLL, 28, 0x12345678LL },
+ { 0x0123456789ABCDEFLL, 29, 0x91A2B3CLL },
+ { 0x0123456789ABCDEFLL, 30, 0x48D159ELL },
+ { 0x0123456789ABCDEFLL, 31, 0x2468ACFLL },
+ { 0x0123456789ABCDEFLL, 32, 0x1234567LL },
+ { 0x0123456789ABCDEFLL, 33, 0x91A2B3LL },
+ { 0x0123456789ABCDEFLL, 34, 0x48D159LL },
+ { 0x0123456789ABCDEFLL, 35, 0x2468ACLL },
+ { 0x0123456789ABCDEFLL, 36, 0x123456LL },
+ { 0x0123456789ABCDEFLL, 60, 0 },
+ { 0x0123456789ABCDEFLL, 61, 0 },
+ { 0x0123456789ABCDEFLL, 62, 0 },
+ { 0x0123456789ABCDEFLL, 63, 0 },
+ { 0xFEDCBA9876543210LL, 0, 0xFEDCBA9876543210LL },
+ { 0xFEDCBA9876543210LL, 1, 0xFF6E5D4C3B2A1908LL },
+ { 0xFEDCBA9876543210LL, 2, 0xFFB72EA61D950C84LL },
+ { 0xFEDCBA9876543210LL, 3, 0xFFDB97530ECA8642LL },
+ { 0xFEDCBA9876543210LL, 4, 0xFFEDCBA987654321LL },
+ { 0xFEDCBA9876543210LL, 28, 0xFFFFFFFFEDCBA987LL },
+ { 0xFEDCBA9876543210LL, 29, 0xFFFFFFFFF6E5D4C3LL },
+ { 0xFEDCBA9876543210LL, 30, 0xFFFFFFFFFB72EA61LL },
+ { 0xFEDCBA9876543210LL, 31, 0xFFFFFFFFFDB97530LL },
+ { 0xFEDCBA9876543210LL, 32, 0xFFFFFFFFFEDCBA98LL },
+ { 0xFEDCBA9876543210LL, 33, 0xFFFFFFFFFF6E5D4CLL },
+ { 0xFEDCBA9876543210LL, 34, 0xFFFFFFFFFFB72EA6LL },
+ { 0xFEDCBA9876543210LL, 35, 0xFFFFFFFFFFDB9753LL },
+ { 0xFEDCBA9876543210LL, 36, 0xFFFFFFFFFFEDCBA9LL },
+ { 0xAEDCBA9876543210LL, 60, 0xFFFFFFFFFFFFFFFALL },
+ { 0xAEDCBA9876543210LL, 61, 0xFFFFFFFFFFFFFFFDLL },
+ { 0xAEDCBA9876543210LL, 62, 0xFFFFFFFFFFFFFFFELL },
+ { 0xAEDCBA9876543210LL, 63, 0xFFFFFFFFFFFFFFFFLL },
+};
+
+static void shdi3_test_ashrdi3(struct kunit *test)
+{
+ const struct shdi3_test_entry *e;
+ long long ret;
+
+ for (e = ashrdi3_testdata;
+ e < ashrdi3_testdata + ARRAY_SIZE(ashrdi3_testdata); e++) {
+ ret = __ashrdi3(e->input, e->shift);
+ KUNIT_EXPECT_EQ_MSG(test, ret, e->result,
+ " when evaluating __ashrdi3(%lld, %d)",
+ e->input, e->shift);
+ }
+}
+
+static const struct shdi3_test_entry lshrdi3_testdata[] = {
+ /* https://github.com/llvm/llvm-project/compiler-rt/test/builtins/Unit/lshrdi3_test.c */
+ { 0x0123456789ABCDEFLL, 0, 0x123456789ABCDEFLL },
+ { 0x0123456789ABCDEFLL, 1, 0x91A2B3C4D5E6F7LL },
+ { 0x0123456789ABCDEFLL, 2, 0x48D159E26AF37BLL },
+ { 0x0123456789ABCDEFLL, 3, 0x2468ACF13579BDLL },
+ { 0x0123456789ABCDEFLL, 4, 0x123456789ABCDELL },
+ { 0x0123456789ABCDEFLL, 28, 0x12345678LL },
+ { 0x0123456789ABCDEFLL, 29, 0x91A2B3CLL },
+ { 0x0123456789ABCDEFLL, 30, 0x48D159ELL },
+ { 0x0123456789ABCDEFLL, 31, 0x2468ACFLL },
+ { 0x0123456789ABCDEFLL, 32, 0x1234567LL },
+ { 0x0123456789ABCDEFLL, 33, 0x91A2B3LL },
+ { 0x0123456789ABCDEFLL, 34, 0x48D159LL },
+ { 0x0123456789ABCDEFLL, 35, 0x2468ACLL },
+ { 0x0123456789ABCDEFLL, 36, 0x123456LL },
+ { 0x0123456789ABCDEFLL, 60, 0 },
+ { 0x0123456789ABCDEFLL, 61, 0 },
+ { 0x0123456789ABCDEFLL, 62, 0 },
+ { 0x0123456789ABCDEFLL, 63, 0 },
+ { 0xFEDCBA9876543210LL, 0, 0xFEDCBA9876543210LL },
+ { 0xFEDCBA9876543210LL, 1, 0x7F6E5D4C3B2A1908LL },
+ { 0xFEDCBA9876543210LL, 2, 0x3FB72EA61D950C84LL },
+ { 0xFEDCBA9876543210LL, 3, 0x1FDB97530ECA8642LL },
+ { 0xFEDCBA9876543210LL, 4, 0xFEDCBA987654321LL },
+ { 0xFEDCBA9876543210LL, 28, 0xFEDCBA987LL },
+ { 0xFEDCBA9876543210LL, 29, 0x7F6E5D4C3LL },
+ { 0xFEDCBA9876543210LL, 30, 0x3FB72EA61LL },
+ { 0xFEDCBA9876543210LL, 31, 0x1FDB97530LL },
+ { 0xFEDCBA9876543210LL, 32, 0xFEDCBA98LL },
+ { 0xFEDCBA9876543210LL, 33, 0x7F6E5D4CLL },
+ { 0xFEDCBA9876543210LL, 34, 0x3FB72EA6LL },
+ { 0xFEDCBA9876543210LL, 35, 0x1FDB9753LL },
+ { 0xFEDCBA9876543210LL, 36, 0xFEDCBA9LL },
+ { 0xAEDCBA9876543210LL, 60, 0xALL },
+ { 0xAEDCBA9876543210LL, 61, 0x5LL },
+ { 0xAEDCBA9876543210LL, 62, 0x2LL },
+ { 0xAEDCBA9876543210LL, 63, 0x1LL },
+};
+
+static void shdi3_test_lshrdi3(struct kunit *test)
+{
+ const struct shdi3_test_entry *e;
+ long long ret;
+
+ for (e = lshrdi3_testdata;
+ e < lshrdi3_testdata + ARRAY_SIZE(lshrdi3_testdata); e++) {
+ ret = __lshrdi3(e->input, e->shift);
+ KUNIT_EXPECT_EQ_MSG(test, ret, e->result,
+ " when evaluating __lshrdi3(%lld, %d)",
+ e->input, e->shift);
+ }
+}
+
+static struct kunit_case shdi3_test_cases[] = {
+ KUNIT_CASE(shdi3_test_ashldi3),
+ KUNIT_CASE(shdi3_test_ashrdi3),
+ KUNIT_CASE(shdi3_test_lshrdi3),
+ {}
+};
+
+static struct kunit_suite shdi3_test_suite = {
+ .name = "shdi3",
+ .test_cases = shdi3_test_cases,
+};
+kunit_test_suite(shdi3_test_suite);
+
+MODULE_DESCRIPTION("Test cases for __ashldi3(), __ashrdi3(), and __lshrdi3()");
+MODULE_LICENSE("GPL");
--
2.53.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v4 3/3] riscv: fix building compressed EFI image
2026-04-14 10:26 [PATCH v4 0/3] riscv32 library enhancements and build fixes Dmitry Antipov
2026-04-14 10:26 ` [PATCH v4 1/3] riscv: add platform-specific double word shifts for riscv32 Dmitry Antipov
2026-04-14 10:26 ` [PATCH v4 2/3] lib: kunit: add tests for __ashldi3(), __ashrdi3(), and __lshrdi3() Dmitry Antipov
@ 2026-04-14 10:26 ` Dmitry Antipov
2026-04-15 9:52 ` Andy Shevchenko
2 siblings, 1 reply; 6+ messages in thread
From: Dmitry Antipov @ 2026-04-14 10:26 UTC (permalink / raw)
To: Andrew Morton
Cc: Andy Shevchenko, Charlie Jenkins, Paul Walmsley, Palmer Dabbelt,
Albert Ou, Ard Biesheuvel, linux-riscv, linux-efi, Dmitry Antipov
When building vmlinuz.efi with CONFIG_EFI_ZBOOT enabled,
'__lshrdi3()' is also needed to fix yet another link error:
riscv32-linux-gnu-ld: drivers/firmware/efi/libstub/lib-cmdline.stub.o: in function `__efistub_.L49':
__efistub_cmdline.c:(.init.text+0x202): undefined reference to `__efistub___lshrdi3'
And since riscv64 can have CONFIG_EFI_ZBOOT but doesn't need these
library routines, introduce CONFIG_EFI_ZBOOT_USE_LIBGCC to manage
linking of lib-ashldi3.o and lib-lshrdi3.o on riscv32 only.
Reported-by: Charlie Jenkins <thecharlesjenkins@gmail.com>
Closes: https://lore.kernel.org/linux-riscv/20260409050018.GA371560@inky.localdomain
Tested-by: Charlie Jenkins <thecharlesjenkins@gmail.com>
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
---
v4: use more meaningful CONFIG_EFI_ZBOOT_USE_LIBGCC and adjust tags (Andy)
v3: initial version to join the series
---
drivers/firmware/efi/Kconfig | 4 ++++
drivers/firmware/efi/libstub/Makefile | 3 ++-
2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index 29e0729299f5b..e1483e20c69b9 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -85,6 +85,10 @@ config EFI_ZBOOT
provided that the loader implements the decompression algorithm.
(The compression algorithm used is described in the zboot header)
+config EFI_ZBOOT_USE_LIBGCC
+ bool
+ default y if RISCV && 32BIT
+
config EFI_ARMSTUB_DTB_LOADER
bool "Enable the DTB loader"
depends on EFI_GENERIC_STUB && !RISCV && !LOONGARCH
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index e386ffd009b7e..91cefa80c158f 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -96,7 +96,8 @@ CFLAGS_zboot-decompress-gzip.o += -I$(srctree)/lib/zlib_inflate
zboot-obj-$(CONFIG_KERNEL_ZSTD) := zboot-decompress-zstd.o lib-xxhash.o
CFLAGS_zboot-decompress-zstd.o += -I$(srctree)/lib/zstd
-zboot-obj-$(CONFIG_RISCV) += lib-clz_ctz.o lib-ashldi3.o
+zboot-libgcc-obj-$(CONFIG_EFI_ZBOOT_USE_LIBGCC) += lib-ashldi3.o lib-lshrdi3.o
+zboot-obj-$(CONFIG_RISCV) += lib-clz_ctz.o $(zboot-libgcc-obj-y)
lib-$(CONFIG_EFI_ZBOOT) += zboot.o $(zboot-obj-y)
lib-$(CONFIG_UNACCEPTED_MEMORY) += unaccepted_memory.o bitmap.o find.o
--
2.53.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v4 3/3] riscv: fix building compressed EFI image
2026-04-14 10:26 ` [PATCH v4 3/3] riscv: fix building compressed EFI image Dmitry Antipov
@ 2026-04-15 9:52 ` Andy Shevchenko
2026-04-15 9:56 ` Ard Biesheuvel
0 siblings, 1 reply; 6+ messages in thread
From: Andy Shevchenko @ 2026-04-15 9:52 UTC (permalink / raw)
To: Dmitry Antipov
Cc: Andrew Morton, Charlie Jenkins, Paul Walmsley, Palmer Dabbelt,
Albert Ou, Ard Biesheuvel, linux-riscv, linux-efi
On Tue, Apr 14, 2026 at 01:26:08PM +0300, Dmitry Antipov wrote:
> When building vmlinuz.efi with CONFIG_EFI_ZBOOT enabled,
> '__lshrdi3()' is also needed to fix yet another link error:
>
> riscv32-linux-gnu-ld: drivers/firmware/efi/libstub/lib-cmdline.stub.o: in function `__efistub_.L49':
> __efistub_cmdline.c:(.init.text+0x202): undefined reference to `__efistub___lshrdi3'
>
> And since riscv64 can have CONFIG_EFI_ZBOOT but doesn't need these
> library routines, introduce CONFIG_EFI_ZBOOT_USE_LIBGCC to manage
> linking of lib-ashldi3.o and lib-lshrdi3.o on riscv32 only.
Acked-by: Andy Shevchenko <andriy.shevchenko@intel.com>
I think you need a tag from Ard on this.
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v4 3/3] riscv: fix building compressed EFI image
2026-04-15 9:52 ` Andy Shevchenko
@ 2026-04-15 9:56 ` Ard Biesheuvel
0 siblings, 0 replies; 6+ messages in thread
From: Ard Biesheuvel @ 2026-04-15 9:56 UTC (permalink / raw)
To: Andy Shevchenko, Dmitry Antipov
Cc: Andrew Morton, Charlie Jenkins, Paul Walmsley, Palmer Dabbelt,
Albert Ou, linux-riscv, linux-efi
On Wed, 15 Apr 2026, at 11:52, Andy Shevchenko wrote:
> On Tue, Apr 14, 2026 at 01:26:08PM +0300, Dmitry Antipov wrote:
>> When building vmlinuz.efi with CONFIG_EFI_ZBOOT enabled,
>> '__lshrdi3()' is also needed to fix yet another link error:
>>
>> riscv32-linux-gnu-ld: drivers/firmware/efi/libstub/lib-cmdline.stub.o: in function `__efistub_.L49':
>> __efistub_cmdline.c:(.init.text+0x202): undefined reference to `__efistub___lshrdi3'
>>
>> And since riscv64 can have CONFIG_EFI_ZBOOT but doesn't need these
>> library routines, introduce CONFIG_EFI_ZBOOT_USE_LIBGCC to manage
>> linking of lib-ashldi3.o and lib-lshrdi3.o on riscv32 only.
>
> Acked-by: Andy Shevchenko <andriy.shevchenko@intel.com>
>
> I think you need a tag from Ard on this.
>
I don't think we need a new Kconfig symbol for this.
Better do something like
zboot-riscv-obj-$(CONFIG_32BIT) += lib-ashldi3.o lib-lshrdi3.o
zboot-obj-$(CONFIG_RISCV) += lib-clz_ctz.o $(zboot-riscv-obj-y)
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2026-04-15 9:57 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-04-14 10:26 [PATCH v4 0/3] riscv32 library enhancements and build fixes Dmitry Antipov
2026-04-14 10:26 ` [PATCH v4 1/3] riscv: add platform-specific double word shifts for riscv32 Dmitry Antipov
2026-04-14 10:26 ` [PATCH v4 2/3] lib: kunit: add tests for __ashldi3(), __ashrdi3(), and __lshrdi3() Dmitry Antipov
2026-04-14 10:26 ` [PATCH v4 3/3] riscv: fix building compressed EFI image Dmitry Antipov
2026-04-15 9:52 ` Andy Shevchenko
2026-04-15 9:56 ` Ard Biesheuvel
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