In preparation for a change to make this test run repeatedly which would generate huge amounts of output as is indirect all the printf() calls in the program through a wrapper and add a quiet flag which can be used to suppress the output. This is fairly quick and dirty, I'm not 100% sure what would be idiomatic here. Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> --- tools/testing/selftests/x86/fsgsbase.c | 52 ++++++++++++++++---------- 1 file changed, 32 insertions(+), 20 deletions(-) diff --git a/tools/testing/selftests/x86/fsgsbase.c b/tools/testing/selftests/x86/fsgsbase.c index f249e042b3b5..6cda6daa1f8c 100644 --- a/tools/testing/selftests/x86/fsgsbase.c +++ b/tools/testing/selftests/x86/fsgsbase.c @@ -7,6 +7,7 @@ #define _GNU_SOURCE #include <stdio.h> #include <stdlib.h> +#include <stdarg.h> #include <stdbool.h> #include <string.h> #include <sys/syscall.h> @@ -32,6 +33,17 @@ static volatile sig_atomic_t want_segv; static volatile unsigned long segv_addr; static int nerrs; +static bool quiet; + +static void logger(const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + if (!quiet) + vprintf(fmt, args); + va_end(args); +} static void sethandler(int sig, void (*handler)(int, siginfo_t *, void *), int flags) @@ -118,29 +130,29 @@ static void check_gs_value(unsigned long value) unsigned long base; unsigned short sel; - printf("[RUN]\tARCH_SET_GS to 0x%lx\n", value); + logger("[RUN]\tARCH_SET_GS to 0x%lx\n", value); if (syscall(SYS_arch_prctl, ARCH_SET_GS, value) != 0) err(1, "ARCH_SET_GS"); asm volatile ("mov %%gs, %0" : "=rm" (sel)); base = read_base(GS); if (base == value) { - printf("[OK]\tGSBASE was set as expected (selector 0x%hx)\n", + logger("[OK]\tGSBASE was set as expected (selector 0x%hx)\n", sel); } else { nerrs++; - printf("[FAIL]\tGSBASE was not as expected: got 0x%lx (selector 0x%hx)\n", + logger("[FAIL]\tGSBASE was not as expected: got 0x%lx (selector 0x%hx)\n", base, sel); } if (syscall(SYS_arch_prctl, ARCH_GET_GS, &base) != 0) err(1, "ARCH_GET_GS"); if (base == value) { - printf("[OK]\tARCH_GET_GS worked as expected (selector 0x%hx)\n", + logger("[OK]\tARCH_GET_GS worked as expected (selector 0x%hx)\n", sel); } else { nerrs++; - printf("[FAIL]\tARCH_GET_GS was not as expected: got 0x%lx (selector 0x%hx)\n", + logger("[FAIL]\tARCH_GET_GS was not as expected: got 0x%lx (selector 0x%hx)\n", base, sel); } } @@ -149,7 +161,7 @@ static void mov_0_gs(unsigned long initial_base, bool schedule) { unsigned long base, arch_base; - printf("[RUN]\tARCH_SET_GS to 0x%lx then mov 0 to %%gs%s\n", initial_base, schedule ? " and schedule " : ""); + logger("[RUN]\tARCH_SET_GS to 0x%lx then mov 0 to %%gs%s\n", initial_base, schedule ? " and schedule " : ""); if (syscall(SYS_arch_prctl, ARCH_SET_GS, initial_base) != 0) err(1, "ARCH_SET_GS"); @@ -161,10 +173,10 @@ static void mov_0_gs(unsigned long initial_base, bool schedule) if (syscall(SYS_arch_prctl, ARCH_GET_GS, &arch_base) != 0) err(1, "ARCH_GET_GS"); if (base == arch_base) { - printf("[OK]\tGSBASE is 0x%lx\n", base); + logger("[OK]\tGSBASE is 0x%lx\n", base); } else { nerrs++; - printf("[FAIL]\tGSBASE changed to 0x%lx but kernel reports 0x%lx\n", base, arch_base); + logger("[FAIL]\tGSBASE changed to 0x%lx but kernel reports 0x%lx\n", base, arch_base); } } @@ -195,7 +207,7 @@ static void do_remote_base() unsigned short sel; asm volatile ("mov %%gs, %0" : "=rm" (sel)); - printf("\tother thread: ARCH_SET_GS(0x%lx)%s -- sel is 0x%hx\n", + logger("\tother thread: ARCH_SET_GS(0x%lx)%s -- sel is 0x%hx\n", to_set, hard_zero ? " and clear gs" : "", sel); } @@ -228,7 +240,7 @@ void do_unexpected_base(void) .useable = 0 }; if (syscall(SYS_modify_ldt, 1, &desc, sizeof(desc)) == 0) { - printf("\tother thread: using LDT slot 0\n"); + logger("\tother thread: using LDT slot 0\n"); asm volatile ("mov %0, %%gs" : : "rm" ((unsigned short)0x7)); } else { /* No modify_ldt for us (configured out, perhaps) */ @@ -250,10 +262,10 @@ void do_unexpected_base(void) munmap(low_desc, sizeof(desc)); if (ret != 0) { - printf("[NOTE]\tcould not create a segment -- test won't do anything\n"); + logger("[NOTE]\tcould not create a segment -- test won't do anything\n"); return; } - printf("\tother thread: using GDT slot %d\n", desc.entry_number); + logger("\tother thread: using GDT slot %d\n", desc.entry_number); asm volatile ("mov %0, %%gs" : : "rm" ((unsigned short)((desc.entry_number << 3) | 0x3))); } @@ -298,10 +310,10 @@ static void set_gs_and_switch_to(unsigned long local, local = 0; } - printf("[RUN]\tARCH_SET_GS(0x%lx)%s, then schedule to 0x%lx\n", + logger("[RUN]\tARCH_SET_GS(0x%lx)%s, then schedule to 0x%lx\n", local, hard_zero ? " and clear gs" : "", remote); if (force_sel) - printf("\tBefore schedule, set selector to 0x%hx\n", force_sel); + logger("\tBefore schedule, set selector to 0x%hx\n", force_sel); if (syscall(SYS_arch_prctl, ARCH_SET_GS, local) != 0) err(1, "ARCH_SET_GS"); if (hard_zero) @@ -309,7 +321,7 @@ static void set_gs_and_switch_to(unsigned long local, if (read_base(GS) != local) { nerrs++; - printf("[FAIL]\tGSBASE wasn't set as expected\n"); + logger("[FAIL]\tGSBASE wasn't set as expected\n"); } if (force_sel) { @@ -335,11 +347,11 @@ static void set_gs_and_switch_to(unsigned long local, asm volatile ("mov %%gs, %0" : "=rm" (sel_post_sched)); base = read_base(GS); if (base == local && sel_pre_sched == sel_post_sched) { - printf("[OK]\tGS/BASE remained 0x%hx/0x%lx\n", + logger("[OK]\tGS/BASE remained 0x%hx/0x%lx\n", sel_pre_sched, local); } else { nerrs++; - printf("[FAIL]\tGS/BASE changed from 0x%hx/0x%lx to 0x%hx/0x%lx\n", + logger("[FAIL]\tGS/BASE changed from 0x%hx/0x%lx to 0x%hx/0x%lx\n", sel_pre_sched, local, sel_post_sched, base); } } @@ -348,7 +360,7 @@ static void test_unexpected_base(void) { unsigned long base; - printf("[RUN]\tARCH_SET_GS(0), clear gs, then manipulate GSBASE in a different thread\n"); + logger("[RUN]\tARCH_SET_GS(0), clear gs, then manipulate GSBASE in a different thread\n"); if (syscall(SYS_arch_prctl, ARCH_SET_GS, 0) != 0) err(1, "ARCH_SET_GS"); asm volatile ("mov %0, %%gs" : : "rm" ((unsigned short)0)); @@ -360,10 +372,10 @@ static void test_unexpected_base(void) base = read_base(GS); if (base == 0) { - printf("[OK]\tGSBASE remained 0\n"); + logger("[OK]\tGSBASE remained 0\n"); } else { nerrs++; - printf("[FAIL]\tGSBASE changed to 0x%lx\n", base); + logger("[FAIL]\tGSBASE changed to 0x%lx\n", base); } } -- 2.20.1