diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-03-25 10:01:34 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-03-25 10:01:34 -0700 |
commit | d710d370c4911e83da5d2bc43d4a2c3b56bd27e7 (patch) | |
tree | 9e7a702654feb88e2555c1bf41f71ef4a58b25aa /arch/s390/lib/test_unwind.c | |
parent | 744465da705f7d8cd893e97738a47b91f3321ce2 (diff) | |
parent | c65f677b62d6180cc174e06f953f7fe860adf6d1 (diff) |
Merge tag 's390-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Vasily Gorbik:
- Raise minimum supported machine generation to z10, which comes with
various cleanups and code simplifications (usercopy/spectre
mitigation/etc).
- Rework extables and get rid of anonymous out-of-line fixups.
- Page table helpers cleanup. Add set_pXd()/set_pte() helper functions.
Covert pte_val()/pXd_val() macros to functions.
- Optimize kretprobe handling by avoiding extra kprobe on
__kretprobe_trampoline.
- Add support for CEX8 crypto cards.
- Allow to trigger AP bus rescan via writing to /sys/bus/ap/scans.
- Add CONFIG_EXPOLINE_EXTERN option to build the kernel without COMDAT
group sections which simplifies kpatch support.
- Always use the packed stack layout and extend kernel unwinder tests.
- Add sanity checks for ftrace code patching.
- Add s390dbf debug log for the vfio_ap device driver.
- Various virtual vs physical address confusion fixes.
- Various small fixes and improvements all over the code.
* tag 's390-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (69 commits)
s390/test_unwind: add kretprobe tests
s390/kprobes: Avoid additional kprobe in kretprobe handling
s390: convert ".insn" encoding to instruction names
s390: assume stckf is always present
s390/nospec: move to single register thunks
s390: raise minimum supported machine generation to z10
s390/uaccess: Add copy_from/to_user_key functions
s390/nospec: align and size extern thunks
s390/nospec: add an option to use thunk-extern
s390/nospec: generate single register thunks if possible
s390/pci: make zpci_set_irq()/zpci_clear_irq() static
s390: remove unused expoline to BC instructions
s390/irq: use assignment instead of cast
s390/traps: get rid of magic cast for per code
s390/traps: get rid of magic cast for program interruption code
s390/signal: fix typo in comments
s390/asm-offsets: remove unused defines
s390/test_unwind: avoid build warning with W=1
s390: remove .fixup section
s390/bpf: encode register within extable entry
...
Diffstat (limited to 'arch/s390/lib/test_unwind.c')
-rw-r--r-- | arch/s390/lib/test_unwind.c | 274 |
1 files changed, 195 insertions, 79 deletions
diff --git a/arch/s390/lib/test_unwind.c b/arch/s390/lib/test_unwind.c index bc7973359ae2..c01f02887de4 100644 --- a/arch/s390/lib/test_unwind.c +++ b/arch/s390/lib/test_unwind.c @@ -8,6 +8,7 @@ #include <linux/completion.h> #include <linux/kallsyms.h> #include <linux/kthread.h> +#include <linux/ftrace.h> #include <linux/module.h> #include <linux/timer.h> #include <linux/slab.h> @@ -16,10 +17,14 @@ #include <linux/wait.h> #include <asm/irq.h> -struct kunit *current_test; +static struct kunit *current_test; #define BT_BUF_SIZE (PAGE_SIZE * 4) +static bool force_bt; +module_param_named(backtrace, force_bt, bool, 0444); +MODULE_PARM_DESC(backtrace, "print backtraces for all tests"); + /* * To avoid printk line limit split backtrace by lines */ @@ -98,7 +103,7 @@ static noinline int test_unwind(struct task_struct *task, struct pt_regs *regs, kunit_err(current_test, "Maximum number of frames exceeded\n"); ret = -EINVAL; } - if (ret) + if (ret || force_bt) print_backtrace(bt); kfree(bt); return ret; @@ -124,7 +129,10 @@ static struct unwindme *unwindme; #define UWM_CALLER 0x8 /* Unwind starting from caller. */ #define UWM_SWITCH_STACK 0x10 /* Use call_on_stack. */ #define UWM_IRQ 0x20 /* Unwind from irq context. */ -#define UWM_PGM 0x40 /* Unwind from program check handler. */ +#define UWM_PGM 0x40 /* Unwind from program check handler */ +#define UWM_KPROBE_ON_FTRACE 0x80 /* Unwind from kprobe handler called via ftrace. */ +#define UWM_FTRACE 0x100 /* Unwind from ftrace handler. */ +#define UWM_KRETPROBE 0x200 /* Unwind kretprobe handlers. */ static __always_inline unsigned long get_psw_addr(void) { @@ -136,8 +144,56 @@ static __always_inline unsigned long get_psw_addr(void) return psw_addr; } -#ifdef CONFIG_KPROBES -static int pgm_pre_handler(struct kprobe *p, struct pt_regs *regs) +static int kretprobe_ret_handler(struct kretprobe_instance *ri, struct pt_regs *regs) +{ + struct unwindme *u = unwindme; + + u->ret = test_unwind(NULL, (u->flags & UWM_REGS) ? regs : NULL, + (u->flags & UWM_SP) ? u->sp : 0); + + return 0; +} + +static noinline notrace void test_unwind_kretprobed_func(void) +{ + asm volatile(" nop\n"); +} + +static noinline void test_unwind_kretprobed_func_caller(void) +{ + test_unwind_kretprobed_func(); +} + +static int test_unwind_kretprobe(struct unwindme *u) +{ + int ret; + struct kretprobe my_kretprobe; + + if (!IS_ENABLED(CONFIG_KPROBES)) + kunit_skip(current_test, "requires CONFIG_KPROBES"); + + u->ret = -1; /* make sure kprobe is called */ + unwindme = u; + + memset(&my_kretprobe, 0, sizeof(my_kretprobe)); + my_kretprobe.handler = kretprobe_ret_handler; + my_kretprobe.maxactive = 1; + my_kretprobe.kp.addr = (kprobe_opcode_t *)test_unwind_kretprobed_func; + + ret = register_kretprobe(&my_kretprobe); + + if (ret < 0) { + kunit_err(current_test, "register_kretprobe failed %d\n", ret); + return -EINVAL; + } + + test_unwind_kretprobed_func_caller(); + unregister_kretprobe(&my_kretprobe); + unwindme = NULL; + return u->ret; +} + +static int kprobe_pre_handler(struct kprobe *p, struct pt_regs *regs) { struct unwindme *u = unwindme; @@ -145,8 +201,97 @@ static int pgm_pre_handler(struct kprobe *p, struct pt_regs *regs) (u->flags & UWM_SP) ? u->sp : 0); return 0; } + +extern const char test_unwind_kprobed_insn[]; + +static noinline void test_unwind_kprobed_func(void) +{ + asm volatile( + " nopr %%r7\n" + "test_unwind_kprobed_insn:\n" + " nopr %%r7\n" + :); +} + +static int test_unwind_kprobe(struct unwindme *u) +{ + struct kprobe kp; + int ret; + + if (!IS_ENABLED(CONFIG_KPROBES)) + kunit_skip(current_test, "requires CONFIG_KPROBES"); + if (!IS_ENABLED(CONFIG_KPROBES_ON_FTRACE) && u->flags & UWM_KPROBE_ON_FTRACE) + kunit_skip(current_test, "requires CONFIG_KPROBES_ON_FTRACE"); + + u->ret = -1; /* make sure kprobe is called */ + unwindme = u; + memset(&kp, 0, sizeof(kp)); + kp.pre_handler = kprobe_pre_handler; + kp.addr = u->flags & UWM_KPROBE_ON_FTRACE ? + (kprobe_opcode_t *)test_unwind_kprobed_func : + (kprobe_opcode_t *)test_unwind_kprobed_insn; + ret = register_kprobe(&kp); + if (ret < 0) { + kunit_err(current_test, "register_kprobe failed %d\n", ret); + return -EINVAL; + } + + test_unwind_kprobed_func(); + unregister_kprobe(&kp); + unwindme = NULL; + return u->ret; +} + +static void notrace __used test_unwind_ftrace_handler(unsigned long ip, + unsigned long parent_ip, + struct ftrace_ops *fops, + struct ftrace_regs *fregs) +{ + struct unwindme *u = (struct unwindme *)fregs->regs.gprs[2]; + + u->ret = test_unwind(NULL, (u->flags & UWM_REGS) ? &fregs->regs : NULL, + (u->flags & UWM_SP) ? u->sp : 0); +} + +static noinline int test_unwind_ftraced_func(struct unwindme *u) +{ + return READ_ONCE(u)->ret; +} + +static int test_unwind_ftrace(struct unwindme *u) +{ + int ret; +#ifdef CONFIG_DYNAMIC_FTRACE + struct ftrace_ops *fops; + + fops = kunit_kzalloc(current_test, sizeof(*fops), GFP_KERNEL); + fops->func = test_unwind_ftrace_handler; + fops->flags = FTRACE_OPS_FL_DYNAMIC | + FTRACE_OPS_FL_RECURSION | + FTRACE_OPS_FL_SAVE_REGS | + FTRACE_OPS_FL_PERMANENT; +#else + kunit_skip(current_test, "requires CONFIG_DYNAMIC_FTRACE"); #endif + ret = ftrace_set_filter_ip(fops, (unsigned long)test_unwind_ftraced_func, 0, 0); + if (ret) { + kunit_err(current_test, "failed to set ftrace filter (%d)\n", ret); + return -1; + } + + ret = register_ftrace_function(fops); + if (!ret) { + ret = test_unwind_ftraced_func(u); + unregister_ftrace_function(fops); + } else { + kunit_err(current_test, "failed to register ftrace handler (%d)\n", ret); + } + + ftrace_set_filter_ip(fops, (unsigned long)test_unwind_ftraced_func, 1, 0); + return ret; +} + /* This function may or may not appear in the backtrace. */ static noinline int unwindme_func4(struct unwindme *u) { @@ -157,35 +302,12 @@ static noinline int unwindme_func4(struct unwindme *u) wait_event(u->task_wq, kthread_should_park()); kthread_parkme(); return 0; -#ifdef CONFIG_KPROBES - } else if (u->flags & UWM_PGM) { - struct kprobe kp; - int ret; - - unwindme = u; - memset(&kp, 0, sizeof(kp)); - kp.symbol_name = "do_report_trap"; - kp.pre_handler = pgm_pre_handler; - ret = register_kprobe(&kp); - if (ret < 0) { - kunit_err(current_test, "register_kprobe failed %d\n", ret); - return -EINVAL; - } - - /* - * Trigger operation exception; use insn notation to bypass - * llvm's integrated assembler sanity checks. - */ - asm volatile( - " .insn e,0x0000\n" /* illegal opcode */ - "0: nopr %%r7\n" - EX_TABLE(0b, 0b) - :); - - unregister_kprobe(&kp); - unwindme = NULL; - return u->ret; -#endif + } else if (u->flags & (UWM_PGM | UWM_KPROBE_ON_FTRACE)) { + return test_unwind_kprobe(u); + } else if (u->flags & (UWM_KRETPROBE)) { + return test_unwind_kretprobe(u); + } else if (u->flags & UWM_FTRACE) { + return test_unwind_ftrace(u); } else { struct pt_regs regs; @@ -255,7 +377,7 @@ static int test_unwind_irq(struct unwindme *u) } /* Spawns a task and passes it to test_unwind(). */ -static int test_unwind_task(struct kunit *test, struct unwindme *u) +static int test_unwind_task(struct unwindme *u) { struct task_struct *task; int ret; @@ -270,7 +392,7 @@ static int test_unwind_task(struct kunit *test, struct unwindme *u) */ task = kthread_run(unwindme_func1, u, "%s", __func__); if (IS_ERR(task)) { - kunit_err(test, "kthread_run() failed\n"); + kunit_err(current_test, "kthread_run() failed\n"); return PTR_ERR(task); } /* @@ -293,49 +415,43 @@ struct test_params { /* * Create required parameter list for tests */ +#define TEST_WITH_FLAGS(f) { .flags = f, .name = #f } static const struct test_params param_list[] = { - {.flags = UWM_DEFAULT, .name = "UWM_DEFAULT"}, - {.flags = UWM_SP, .name = "UWM_SP"}, - {.flags = UWM_REGS, .name = "UWM_REGS"}, - {.flags = UWM_SWITCH_STACK, - .name = "UWM_SWITCH_STACK"}, - {.flags = UWM_SP | UWM_REGS, - .name = "UWM_SP | UWM_REGS"}, - {.flags = UWM_CALLER | UWM_SP, - .name = "WM_CALLER | UWM_SP"}, - {.flags = UWM_CALLER | UWM_SP | UWM_REGS, - .name = "UWM_CALLER | UWM_SP | UWM_REGS"}, - {.flags = UWM_CALLER | UWM_SP | UWM_REGS | UWM_SWITCH_STACK, - .name = "UWM_CALLER | UWM_SP | UWM_REGS | UWM_SWITCH_STACK"}, - {.flags = UWM_THREAD, .name = "UWM_THREAD"}, - {.flags = UWM_THREAD | UWM_SP, - .name = "UWM_THREAD | UWM_SP"}, - {.flags = UWM_THREAD | UWM_CALLER | UWM_SP, - .name = "UWM_THREAD | UWM_CALLER | UWM_SP"}, - {.flags = UWM_IRQ, .name = "UWM_IRQ"}, - {.flags = UWM_IRQ | UWM_SWITCH_STACK, - .name = "UWM_IRQ | UWM_SWITCH_STACK"}, - {.flags = UWM_IRQ | UWM_SP, - .name = "UWM_IRQ | UWM_SP"}, - {.flags = UWM_IRQ | UWM_REGS, - .name = "UWM_IRQ | UWM_REGS"}, - {.flags = UWM_IRQ | UWM_SP | UWM_REGS, - .name = "UWM_IRQ | UWM_SP | UWM_REGS"}, - {.flags = UWM_IRQ | UWM_CALLER | UWM_SP, - .name = "UWM_IRQ | UWM_CALLER | UWM_SP"}, - {.flags = UWM_IRQ | UWM_CALLER | UWM_SP | UWM_REGS, - .name = "UWM_IRQ | UWM_CALLER | UWM_SP | UWM_REGS"}, - {.flags = UWM_IRQ | UWM_CALLER | UWM_SP | UWM_REGS | UWM_SWITCH_STACK, - .name = "UWM_IRQ | UWM_CALLER | UWM_SP | UWM_REGS | UWM_SWITCH_STACK"}, - #ifdef CONFIG_KPROBES - {.flags = UWM_PGM, .name = "UWM_PGM"}, - {.flags = UWM_PGM | UWM_SP, - .name = "UWM_PGM | UWM_SP"}, - {.flags = UWM_PGM | UWM_REGS, - .name = "UWM_PGM | UWM_REGS"}, - {.flags = UWM_PGM | UWM_SP | UWM_REGS, - .name = "UWM_PGM | UWM_SP | UWM_REGS"}, - #endif + TEST_WITH_FLAGS(UWM_DEFAULT), + TEST_WITH_FLAGS(UWM_SP), + TEST_WITH_FLAGS(UWM_REGS), + TEST_WITH_FLAGS(UWM_SWITCH_STACK), + TEST_WITH_FLAGS(UWM_SP | UWM_REGS), + TEST_WITH_FLAGS(UWM_CALLER | UWM_SP), + TEST_WITH_FLAGS(UWM_CALLER | UWM_SP | UWM_REGS), + TEST_WITH_FLAGS(UWM_CALLER | UWM_SP | UWM_REGS | UWM_SWITCH_STACK), + TEST_WITH_FLAGS(UWM_THREAD), + TEST_WITH_FLAGS(UWM_THREAD | UWM_SP), + TEST_WITH_FLAGS(UWM_THREAD | UWM_CALLER | UWM_SP), + TEST_WITH_FLAGS(UWM_IRQ), + TEST_WITH_FLAGS(UWM_IRQ | UWM_SWITCH_STACK), + TEST_WITH_FLAGS(UWM_IRQ | UWM_SP), + TEST_WITH_FLAGS(UWM_IRQ | UWM_REGS), + TEST_WITH_FLAGS(UWM_IRQ | UWM_SP | UWM_REGS), + TEST_WITH_FLAGS(UWM_IRQ | UWM_CALLER | UWM_SP), + TEST_WITH_FLAGS(UWM_IRQ | UWM_CALLER | UWM_SP | UWM_REGS), + TEST_WITH_FLAGS(UWM_IRQ | UWM_CALLER | UWM_SP | UWM_REGS | UWM_SWITCH_STACK), + TEST_WITH_FLAGS(UWM_PGM), + TEST_WITH_FLAGS(UWM_PGM | UWM_SP), + TEST_WITH_FLAGS(UWM_PGM | UWM_REGS), + TEST_WITH_FLAGS(UWM_PGM | UWM_SP | UWM_REGS), + TEST_WITH_FLAGS(UWM_KPROBE_ON_FTRACE), + TEST_WITH_FLAGS(UWM_KPROBE_ON_FTRACE | UWM_SP), + TEST_WITH_FLAGS(UWM_KPROBE_ON_FTRACE | UWM_REGS), + TEST_WITH_FLAGS(UWM_KPROBE_ON_FTRACE | UWM_SP | UWM_REGS), + TEST_WITH_FLAGS(UWM_FTRACE), + TEST_WITH_FLAGS(UWM_FTRACE | UWM_SP), + TEST_WITH_FLAGS(UWM_FTRACE | UWM_REGS), + TEST_WITH_FLAGS(UWM_FTRACE | UWM_SP | UWM_REGS), + TEST_WITH_FLAGS(UWM_KRETPROBE), + TEST_WITH_FLAGS(UWM_KRETPROBE | UWM_SP), + TEST_WITH_FLAGS(UWM_KRETPROBE | UWM_REGS), + TEST_WITH_FLAGS(UWM_KRETPROBE | UWM_SP | UWM_REGS), }; /* @@ -360,7 +476,7 @@ static void test_unwind_flags(struct kunit *test) params = (const struct test_params *)test->param_value; u.flags = params->flags; if (u.flags & UWM_THREAD) - KUNIT_EXPECT_EQ(test, 0, test_unwind_task(test, &u)); + KUNIT_EXPECT_EQ(test, 0, test_unwind_task(&u)); else if (u.flags & UWM_IRQ) KUNIT_EXPECT_EQ(test, 0, test_unwind_irq(&u)); else |