From 20a9af057cd7c4057c72c803dcf83c97eb5deb95 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Thu, 22 Aug 2024 09:13:21 +0200 Subject: selftests: vDSO: don't hard-code location of vDSO sources Architectures use different location for vDSO sources: arch/mips/vdso arch/sparc/vdso arch/arm64/kernel/vdso arch/riscv/kernel/vdso arch/csky/kernel/vdso arch/x86/um/vdso arch/x86/entry/vdso arch/powerpc/kernel/vdso arch/arm/vdso arch/loongarch/vdso Don't hard-code vdso sources location in selftest Makefile. Instead create a vdso/ symbolic link in tools/arch/$arch/ and update Makefile accordingly. Signed-off-by: Christophe Leroy Signed-off-by: Jason A. Donenfeld --- tools/arch/x86/vdso | 1 + 1 file changed, 1 insertion(+) create mode 120000 tools/arch/x86/vdso (limited to 'tools/arch') diff --git a/tools/arch/x86/vdso b/tools/arch/x86/vdso new file mode 120000 index 000000000000..7eb962fd3454 --- /dev/null +++ b/tools/arch/x86/vdso @@ -0,0 +1 @@ +../../../arch/x86/entry/vdso/ \ No newline at end of file -- cgit v1.2.3 From 18efd0b10e0fd77fe649a375f9f17a387b5d1609 Mon Sep 17 00:00:00 2001 From: Xi Ruoyao Date: Sun, 1 Sep 2024 14:13:11 +0800 Subject: LoongArch: vDSO: Wire up getrandom() vDSO implementation Hook up the generic vDSO implementation to the LoongArch vDSO data page by providing the required __arch_chacha20_blocks_nostack, __arch_get_k_vdso_rng_data, and getrandom_syscall implementations. Also wire up the selftests. Signed-off-by: Xi Ruoyao Acked-by: Huacai Chen Signed-off-by: Jason A. Donenfeld --- tools/arch/loongarch/vdso | 1 + 1 file changed, 1 insertion(+) create mode 120000 tools/arch/loongarch/vdso (limited to 'tools/arch') diff --git a/tools/arch/loongarch/vdso b/tools/arch/loongarch/vdso new file mode 120000 index 000000000000..ebda43a82db7 --- /dev/null +++ b/tools/arch/loongarch/vdso @@ -0,0 +1 @@ +../../../arch/loongarch/vdso \ No newline at end of file -- cgit v1.2.3 From 712676ea2bb3882a852bcf49862c4247317fc9b2 Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Tue, 3 Sep 2024 12:09:17 +0000 Subject: arm64: vDSO: Wire up getrandom() vDSO implementation Hook up the generic vDSO implementation to the aarch64 vDSO data page. The _vdso_rng_data required data is placed within the _vdso_data vvar page, by using a offset larger than the vdso_data. The vDSO function requires a ChaCha20 implementation that does not write to the stack, and that can do an entire ChaCha20 permutation. The one provided uses NEON on the permute operation, with a fallback to the syscall for chips that do not support AdvSIMD. This also passes the vdso_test_chacha test along with vdso_test_getrandom. The vdso_test_getrandom bench-single result on Neoverse-N1 shows: vdso: 25000000 times in 0.783884250 seconds libc: 25000000 times in 8.780275399 seconds syscall: 25000000 times in 8.786581518 seconds A small fixup to arch/arm64/include/asm/mman.h was required to avoid pulling kernel code into the vDSO, similar to what's already done in arch/arm64/include/asm/rwonce.h. Signed-off-by: Adhemerval Zanella Reviewed-by: Ard Biesheuvel Acked-by: Will Deacon Signed-off-by: Jason A. Donenfeld --- tools/arch/arm64/vdso | 1 + 1 file changed, 1 insertion(+) create mode 120000 tools/arch/arm64/vdso (limited to 'tools/arch') diff --git a/tools/arch/arm64/vdso b/tools/arch/arm64/vdso new file mode 120000 index 000000000000..233c7a26f6e5 --- /dev/null +++ b/tools/arch/arm64/vdso @@ -0,0 +1 @@ +../../../arch/arm64/kernel/vdso \ No newline at end of file -- cgit v1.2.3 From 53cee505ae0c4d19a2c894501a363782410c4a29 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Mon, 2 Sep 2024 21:17:21 +0200 Subject: powerpc/vdso: Wire up getrandom() vDSO implementation on VDSO32 To be consistent with other VDSO functions, the function is called __kernel_getrandom() __arch_chacha20_blocks_nostack() fonction is implemented basically with 32 bits operations. It performs 4 QUARTERROUND operations in parallele. There are enough registers to avoid using the stack: On input: r3: output bytes r4: 32-byte key input r5: 8-byte counter input/output r6: number of 64-byte blocks to write to output During operation: stack: pointer to counter (r5) and non-volatile registers (r14-131) r0: counter of blocks (initialised with r6) r4: Value '4' after key has been read, used for indexing r5-r12: key r14-r15: block counter r16-r31: chacha state At the end: r0, r6-r12: Zeroised r5, r14-r31: Restored Performance on powerpc 885 (using kernel selftest): ~# ./vdso_test_getrandom bench-single vdso: 25000000 times in 62.938002291 seconds libc: 25000000 times in 535.581916866 seconds syscall: 25000000 times in 531.525042806 seconds Performance on powerpc 8321 (using kernel selftest): ~# ./vdso_test_getrandom bench-single vdso: 25000000 times in 16.899318858 seconds libc: 25000000 times in 131.050596522 seconds syscall: 25000000 times in 129.794790389 seconds This first patch adds support for VDSO32. As selftests cannot easily be generated only for VDSO32, and because the following patch brings support for VDSO64 anyway, this patch opts out all code in __arch_chacha20_blocks_nostack() so that vdso_test_chacha will not fail to compile and will not crash on PPC64/PPC64LE, allthough the selftest itself will fail. Signed-off-by: Christophe Leroy Acked-by: Michael Ellerman Signed-off-by: Jason A. Donenfeld --- tools/arch/powerpc/vdso | 1 + 1 file changed, 1 insertion(+) create mode 120000 tools/arch/powerpc/vdso (limited to 'tools/arch') diff --git a/tools/arch/powerpc/vdso b/tools/arch/powerpc/vdso new file mode 120000 index 000000000000..4e676d1d1cb4 --- /dev/null +++ b/tools/arch/powerpc/vdso @@ -0,0 +1 @@ +../../../arch/powerpc/kernel/vdso \ No newline at end of file -- cgit v1.2.3 From b920aa77be6d57d407b6b6be5d8b4ccc17749cce Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Fri, 13 Sep 2024 15:05:43 +0200 Subject: s390/vdso: Wire up getrandom() vdso implementation Provide the s390 specific vdso getrandom() architecture backend. _vdso_rng_data required data is placed within the _vdso_data vvar page, by using a hardcoded offset larger than vdso_data. As required the chacha20 implementation does not write to the stack. The implementation follows more or less the arm64 implementations and makes use of vector instructions. It has a fallback to the getrandom() system call for machines where the vector facility is not installed. The check if the vector facility is installed, as well as an optimization for machines with the vector-enhancements facility 2, is implemented with alternatives, avoiding runtime checks. Note that __kernel_getrandom() is implemented without the vdso user wrapper which would setup a stack frame for odd cases (aka very old glibc variants) where the caller has not done that. All callers of __kernel_getrandom() are required to setup a stack frame, like the C ABI requires it. The vdso testcases vdso_test_getrandom and vdso_test_chacha pass. Benchmark on a z16: $ ./vdso_test_getrandom bench-single vdso: 25000000 times in 0.493703559 seconds syscall: 25000000 times in 6.584025337 seconds Signed-off-by: Heiko Carstens Reviewed-by: Harald Freudenberger Signed-off-by: Jason A. Donenfeld --- tools/arch/s390/vdso | 1 + 1 file changed, 1 insertion(+) create mode 120000 tools/arch/s390/vdso (limited to 'tools/arch') diff --git a/tools/arch/s390/vdso b/tools/arch/s390/vdso new file mode 120000 index 000000000000..6cf4c1cebdcd --- /dev/null +++ b/tools/arch/s390/vdso @@ -0,0 +1 @@ +../../../arch/s390/kernel/vdso64 \ No newline at end of file -- cgit v1.2.3