Björn Töpel 81a1dd10b0 riscv, lib: Fix Zbb strncmp ... The Zbb optimized strncmp has two parts; a fast path that does XLEN/8B per iteration, and a slow that does one byte per iteration. The idea is to compare aligned XLEN chunks for most of strings, and do the remainder tail in the slow path. The Zbb strncmp has two issues in the fast path: Incorrect remainder handling (wrong compare): Assume that the string length is 9. On 64b systems, the fast path should do one iteration, and one iteration in the slow path. Instead, both were done in the fast path, which lead to incorrect results. An example: strncmp("/dev/vda", "/dev/", 5); Correct by changing "bgt" to "bge". Missing NULL checks in the second string: This could lead to incorrect results for: strncmp("/dev/vda", "/dev/vda\0", 8); Correct by adding an additional check. Fixes: b6fcdb191e ("RISC-V: add zbb support to string functions") Suggested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Signed-off-by: Björn Töpel <bjorn@rivosinc.com> Tested-by: Conor Dooley <conor.dooley@microchip.com> Tested-by: Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20230228184211.1585641-1-bjorn@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>		2023-02-28 18:42:38 -08:00
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boot	SoC: DT changes for 6.3	2023-02-20 15:49:56 -08:00
configs	riscv: defconfig: Enable the Allwinner D1 platform and drivers	2023-01-27 23:10:08 +01:00
errata	RISC-V: take text_mutex during alternative patching	2023-02-21 17:21:33 -08:00
include	RISC-V Patches for the 6.3 Merge Window, Part 1	2023-02-25 11:14:08 -08:00
kernel	RISC-V Patches for the 6.3 Merge Window, Part 1	2023-02-25 11:14:08 -08:00
kvm	riscv: KVM: Switch has_svinval() to riscv_has_extension_unlikely()	2023-01-31 23:29:44 -08:00
lib	riscv, lib: Fix Zbb strncmp	2023-02-28 18:42:38 -08:00
mm	RISC-V Patches for the 6.3 Merge Window, Part 1	2023-02-25 11:14:08 -08:00
net	riscv, bpf: Add bpf trampoline support for RV64	2023-02-17 21:45:30 +01:00
purgatory	RISC-V: add infrastructure to allow different str* implementations	2023-01-31 11:43:23 -08:00
Kbuild	riscv: move errata/ and kvm/ builds to arch/riscv/Kbuild	2022-06-01 22:26:32 -07:00
Kconfig	RISC-V Patches for the 6.3 Merge Window, Part 1	2023-02-25 11:14:08 -08:00
Kconfig.debug	RISC-V: Remove EARLY_PRINTK support	2018-12-17 10:23:46 -08:00
Kconfig.erratas	drivers/perf: riscv_pmu_sbi: add support for PMU variant on T-Head C9xx cores	2022-10-27 14:35:20 -07:00
Kconfig.socs	RISC-V Patches for the 6.3 Merge Window, Part 1	2023-02-25 11:14:08 -08:00
Makefile	RISC-V Patches for the 6.3 Merge Window, Part 1	2023-02-25 11:14:08 -08:00