Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 461 insertions, 0 deletions

diff --git a/arch/powerpc/math-emu/math.c b/arch/powerpc/math-emu/math.c
new file mode 100644
index 000000000..936a9a149
--- /dev/null
+++ b/arch/powerpc/math-emu/math.c
@@ -0,0 +1,461 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 1999  Eddie C. Dost  (ecd@atecom.com)
+ */
+
+#include <linux/types.h>
+#include <linux/sched.h>
+
+#include <linux/uaccess.h>
+#include <asm/reg.h>
+#include <asm/switch_to.h>
+
+#include <asm/sfp-machine.h>
+#include <math-emu/double.h>
+
+#define FLOATFUNC(x)	extern int x(void *, void *, void *, void *)
+
+/* The instructions list which may be not implemented by a hardware FPU */
+FLOATFUNC(fre);
+FLOATFUNC(frsqrtes);
+FLOATFUNC(fsqrt);
+FLOATFUNC(fsqrts);
+FLOATFUNC(mtfsf);
+FLOATFUNC(mtfsfi);
+
+#ifdef CONFIG_MATH_EMULATION_HW_UNIMPLEMENTED
+#undef FLOATFUNC
+#define FLOATFUNC(x)	static inline int x(void *op1, void *op2, void *op3, \
+						 void *op4) { return 0; }
+#endif
+
+FLOATFUNC(fadd);
+FLOATFUNC(fadds);
+FLOATFUNC(fdiv);
+FLOATFUNC(fdivs);
+FLOATFUNC(fmul);
+FLOATFUNC(fmuls);
+FLOATFUNC(fsub);
+FLOATFUNC(fsubs);
+
+FLOATFUNC(fmadd);
+FLOATFUNC(fmadds);
+FLOATFUNC(fmsub);
+FLOATFUNC(fmsubs);
+FLOATFUNC(fnmadd);
+FLOATFUNC(fnmadds);
+FLOATFUNC(fnmsub);
+FLOATFUNC(fnmsubs);
+
+FLOATFUNC(fctiw);
+FLOATFUNC(fctiwz);
+FLOATFUNC(frsp);
+
+FLOATFUNC(fcmpo);
+FLOATFUNC(fcmpu);
+
+FLOATFUNC(mcrfs);
+FLOATFUNC(mffs);
+FLOATFUNC(mtfsb0);
+FLOATFUNC(mtfsb1);
+
+FLOATFUNC(lfd);
+FLOATFUNC(lfs);
+
+FLOATFUNC(stfd);
+FLOATFUNC(stfs);
+FLOATFUNC(stfiwx);
+
+FLOATFUNC(fabs);
+FLOATFUNC(fmr);
+FLOATFUNC(fnabs);
+FLOATFUNC(fneg);
+
+/* Optional */
+FLOATFUNC(fres);
+FLOATFUNC(frsqrte);
+FLOATFUNC(fsel);
+
+
+#define OP31		0x1f		/*   31 */
+#define LFS		0x30		/*   48 */
+#define LFSU		0x31		/*   49 */
+#define LFD		0x32		/*   50 */
+#define LFDU		0x33		/*   51 */
+#define STFS		0x34		/*   52 */
+#define STFSU		0x35		/*   53 */
+#define STFD		0x36		/*   54 */
+#define STFDU		0x37		/*   55 */
+#define OP59		0x3b		/*   59 */
+#define OP63		0x3f		/*   63 */
+
+/* Opcode 31: */
+/* X-Form: */
+#define LFSX		0x217		/*  535 */
+#define LFSUX		0x237		/*  567 */
+#define LFDX		0x257		/*  599 */
+#define LFDUX		0x277		/*  631 */
+#define STFSX		0x297		/*  663 */
+#define STFSUX		0x2b7		/*  695 */
+#define STFDX		0x2d7		/*  727 */
+#define STFDUX		0x2f7		/*  759 */
+#define STFIWX		0x3d7		/*  983 */
+
+/* Opcode 59: */
+/* A-Form: */
+#define FDIVS		0x012		/*   18 */
+#define FSUBS		0x014		/*   20 */
+#define FADDS		0x015		/*   21 */
+#define FSQRTS		0x016		/*   22 */
+#define FRES		0x018		/*   24 */
+#define FMULS		0x019		/*   25 */
+#define FRSQRTES	0x01a		/*   26 */
+#define FMSUBS		0x01c		/*   28 */
+#define FMADDS		0x01d		/*   29 */
+#define FNMSUBS		0x01e		/*   30 */
+#define FNMADDS		0x01f		/*   31 */
+
+/* Opcode 63: */
+/* A-Form: */
+#define FDIV		0x012		/*   18 */
+#define FSUB		0x014		/*   20 */
+#define FADD		0x015		/*   21 */
+#define FSQRT		0x016		/*   22 */
+#define FSEL		0x017		/*   23 */
+#define FRE		0x018		/*   24 */
+#define FMUL		0x019		/*   25 */
+#define FRSQRTE		0x01a		/*   26 */
+#define FMSUB		0x01c		/*   28 */
+#define FMADD		0x01d		/*   29 */
+#define FNMSUB		0x01e		/*   30 */
+#define FNMADD		0x01f		/*   31 */
+
+/* X-Form: */
+#define FCMPU		0x000		/*    0	*/
+#define FRSP		0x00c		/*   12 */
+#define FCTIW		0x00e		/*   14 */
+#define FCTIWZ		0x00f		/*   15 */
+#define FCMPO		0x020		/*   32 */
+#define MTFSB1		0x026		/*   38 */
+#define FNEG		0x028		/*   40 */
+#define MCRFS		0x040		/*   64 */
+#define MTFSB0		0x046		/*   70 */
+#define FMR		0x048		/*   72 */
+#define MTFSFI		0x086		/*  134 */
+#define FNABS		0x088		/*  136 */
+#define FABS		0x108		/*  264 */
+#define MFFS		0x247		/*  583 */
+#define MTFSF		0x2c7		/*  711 */
+
+
+#define AB	2
+#define AC	3
+#define ABC	4
+#define D	5
+#define DU	6
+#define X	7
+#define XA	8
+#define XB	9
+#define XCR	11
+#define XCRB	12
+#define XCRI	13
+#define XCRL	16
+#define XE	14
+#define XEU	15
+#define XFLB	10
+
+static int
+record_exception(struct pt_regs *regs, int eflag)
+{
+	u32 fpscr;
+
+	fpscr = __FPU_FPSCR;
+
+	if (eflag) {
+		fpscr |= FPSCR_FX;
+		if (eflag & EFLAG_OVERFLOW)
+			fpscr |= FPSCR_OX;
+		if (eflag & EFLAG_UNDERFLOW)
+			fpscr |= FPSCR_UX;
+		if (eflag & EFLAG_DIVZERO)
+			fpscr |= FPSCR_ZX;
+		if (eflag & EFLAG_INEXACT)
+			fpscr |= FPSCR_XX;
+		if (eflag & EFLAG_INVALID)
+			fpscr |= FPSCR_VX;
+		if (eflag & EFLAG_VXSNAN)
+			fpscr |= FPSCR_VXSNAN;
+		if (eflag & EFLAG_VXISI)
+			fpscr |= FPSCR_VXISI;
+		if (eflag & EFLAG_VXIDI)
+			fpscr |= FPSCR_VXIDI;
+		if (eflag & EFLAG_VXZDZ)
+			fpscr |= FPSCR_VXZDZ;
+		if (eflag & EFLAG_VXIMZ)
+			fpscr |= FPSCR_VXIMZ;
+		if (eflag & EFLAG_VXVC)
+			fpscr |= FPSCR_VXVC;
+		if (eflag & EFLAG_VXSOFT)
+			fpscr |= FPSCR_VXSOFT;
+		if (eflag & EFLAG_VXSQRT)
+			fpscr |= FPSCR_VXSQRT;
+		if (eflag & EFLAG_VXCVI)
+			fpscr |= FPSCR_VXCVI;
+	}
+
+//	fpscr &= ~(FPSCR_VX);
+	if (fpscr & (FPSCR_VXSNAN | FPSCR_VXISI | FPSCR_VXIDI |
+		     FPSCR_VXZDZ | FPSCR_VXIMZ | FPSCR_VXVC |
+		     FPSCR_VXSOFT | FPSCR_VXSQRT | FPSCR_VXCVI))
+		fpscr |= FPSCR_VX;
+
+	fpscr &= ~(FPSCR_FEX);
+	if (((fpscr & FPSCR_VX) && (fpscr & FPSCR_VE)) ||
+	    ((fpscr & FPSCR_OX) && (fpscr & FPSCR_OE)) ||
+	    ((fpscr & FPSCR_UX) && (fpscr & FPSCR_UE)) ||
+	    ((fpscr & FPSCR_ZX) && (fpscr & FPSCR_ZE)) ||
+	    ((fpscr & FPSCR_XX) && (fpscr & FPSCR_XE)))
+		fpscr |= FPSCR_FEX;
+
+	__FPU_FPSCR = fpscr;
+
+	return (fpscr & FPSCR_FEX) ? 1 : 0;
+}
+
+int
+do_mathemu(struct pt_regs *regs)
+{
+	void *op0 = NULL, *op1 = NULL, *op2 = NULL, *op3 = NULL;
+	unsigned long pc = regs->nip;
+	signed short sdisp;
+	u32 insn = 0;
+	int idx = 0;
+	int (*func)(void *, void *, void *, void *);
+	int type = 0;
+	int eflag, trap;
+
+	if (get_user(insn, (u32 __user *)pc))
+		return -EFAULT;
+
+	switch (insn >> 26) {
+	case LFS:	func = lfs;	type = D;	break;
+	case LFSU:	func = lfs;	type = DU;	break;
+	case LFD:	func = lfd;	type = D;	break;
+	case LFDU:	func = lfd;	type = DU;	break;
+	case STFS:	func = stfs;	type = D;	break;
+	case STFSU:	func = stfs;	type = DU;	break;
+	case STFD:	func = stfd;	type = D;	break;
+	case STFDU:	func = stfd;	type = DU;	break;
+
+	case OP31:
+		switch ((insn >> 1) & 0x3ff) {
+		case LFSX:	func = lfs;	type = XE;	break;
+		case LFSUX:	func = lfs;	type = XEU;	break;
+		case LFDX:	func = lfd;	type = XE;	break;
+		case LFDUX:	func = lfd;	type = XEU;	break;
+		case STFSX:	func = stfs;	type = XE;	break;
+		case STFSUX:	func = stfs;	type = XEU;	break;
+		case STFDX:	func = stfd;	type = XE;	break;
+		case STFDUX:	func = stfd;	type = XEU;	break;
+		case STFIWX:	func = stfiwx;	type = XE;	break;
+		default:
+			goto illegal;
+		}
+		break;
+
+	case OP59:
+		switch ((insn >> 1) & 0x1f) {
+		case FDIVS:	func = fdivs;	type = AB;	break;
+		case FSUBS:	func = fsubs;	type = AB;	break;
+		case FADDS:	func = fadds;	type = AB;	break;
+		case FSQRTS:	func = fsqrts;	type = XB;	break;
+		case FRES:	func = fres;	type = XB;	break;
+		case FMULS:	func = fmuls;	type = AC;	break;
+		case FRSQRTES:	func = frsqrtes;type = XB;	break;
+		case FMSUBS:	func = fmsubs;	type = ABC;	break;
+		case FMADDS:	func = fmadds;	type = ABC;	break;
+		case FNMSUBS:	func = fnmsubs;	type = ABC;	break;
+		case FNMADDS:	func = fnmadds;	type = ABC;	break;
+		default:
+			goto illegal;
+		}
+		break;
+
+	case OP63:
+		if (insn & 0x20) {
+			switch ((insn >> 1) & 0x1f) {
+			case FDIV:	func = fdiv;	type = AB;	break;
+			case FSUB:	func = fsub;	type = AB;	break;
+			case FADD:	func = fadd;	type = AB;	break;
+			case FSQRT:	func = fsqrt;	type = XB;	break;
+			case FRE:	func = fre;	type = XB;	break;
+			case FSEL:	func = fsel;	type = ABC;	break;
+			case FMUL:	func = fmul;	type = AC;	break;
+			case FRSQRTE:	func = frsqrte;	type = XB;	break;
+			case FMSUB:	func = fmsub;	type = ABC;	break;
+			case FMADD:	func = fmadd;	type = ABC;	break;
+			case FNMSUB:	func = fnmsub;	type = ABC;	break;
+			case FNMADD:	func = fnmadd;	type = ABC;	break;
+			default:
+				goto illegal;
+			}
+			break;
+		}
+
+		switch ((insn >> 1) & 0x3ff) {
+		case FCMPU:	func = fcmpu;	type = XCR;	break;
+		case FRSP:	func = frsp;	type = XB;	break;
+		case FCTIW:	func = fctiw;	type = XB;	break;
+		case FCTIWZ:	func = fctiwz;	type = XB;	break;
+		case FCMPO:	func = fcmpo;	type = XCR;	break;
+		case MTFSB1:	func = mtfsb1;	type = XCRB;	break;
+		case FNEG:	func = fneg;	type = XB;	break;
+		case MCRFS:	func = mcrfs;	type = XCRL;	break;
+		case MTFSB0:	func = mtfsb0;	type = XCRB;	break;
+		case FMR:	func = fmr;	type = XB;	break;
+		case MTFSFI:	func = mtfsfi;	type = XCRI;	break;
+		case FNABS:	func = fnabs;	type = XB;	break;
+		case FABS:	func = fabs;	type = XB;	break;
+		case MFFS:	func = mffs;	type = X;	break;
+		case MTFSF:	func = mtfsf;	type = XFLB;	break;
+		default:
+			goto illegal;
+		}
+		break;
+
+	default:
+		goto illegal;
+	}
+
+	switch (type) {
+	case AB:
+		op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+		op1 = (void *)&current->thread.TS_FPR((insn >> 16) & 0x1f);
+		op2 = (void *)&current->thread.TS_FPR((insn >> 11) & 0x1f);
+		break;
+
+	case AC:
+		op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+		op1 = (void *)&current->thread.TS_FPR((insn >> 16) & 0x1f);
+		op2 = (void *)&current->thread.TS_FPR((insn >>  6) & 0x1f);
+		break;
+
+	case ABC:
+		op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+		op1 = (void *)&current->thread.TS_FPR((insn >> 16) & 0x1f);
+		op2 = (void *)&current->thread.TS_FPR((insn >> 11) & 0x1f);
+		op3 = (void *)&current->thread.TS_FPR((insn >>  6) & 0x1f);
+		break;
+
+	case D:
+		idx = (insn >> 16) & 0x1f;
+		sdisp = (insn & 0xffff);
+		op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+		op1 = (void *)((idx ? regs->gpr[idx] : 0) + sdisp);
+		break;
+
+	case DU:
+		idx = (insn >> 16) & 0x1f;
+		if (!idx)
+			goto illegal;
+
+		sdisp = (insn & 0xffff);
+		op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+		op1 = (void *)(regs->gpr[idx] + sdisp);
+		break;
+
+	case X:
+		op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+		break;
+
+	case XA:
+		op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+		op1 = (void *)&current->thread.TS_FPR((insn >> 16) & 0x1f);
+		break;
+
+	case XB:
+		op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+		op1 = (void *)&current->thread.TS_FPR((insn >> 11) & 0x1f);
+		break;
+
+	case XE:
+		idx = (insn >> 16) & 0x1f;
+		op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+		op1 = (void *)((idx ? regs->gpr[idx] : 0)
+				+ regs->gpr[(insn >> 11) & 0x1f]);
+		break;
+
+	case XEU:
+		idx = (insn >> 16) & 0x1f;
+		if (!idx)
+			goto illegal;
+		op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+		op1 = (void *)(regs->gpr[idx]
+				+ regs->gpr[(insn >> 11) & 0x1f]);
+		break;
+
+	case XCR:
+		op0 = (void *)&regs->ccr;
+		op1 = (void *)(long)((insn >> 23) & 0x7);
+		op2 = (void *)&current->thread.TS_FPR((insn >> 16) & 0x1f);
+		op3 = (void *)&current->thread.TS_FPR((insn >> 11) & 0x1f);
+		break;
+
+	case XCRL:
+		op0 = (void *)&regs->ccr;
+		op1 = (void *)(long)((insn >> 23) & 0x7);
+		op2 = (void *)(long)((insn >> 18) & 0x7);
+		break;
+
+	case XCRB:
+		op0 = (void *)(long)((insn >> 21) & 0x1f);
+		break;
+
+	case XCRI:
+		op0 = (void *)(long)((insn >> 23) & 0x7);
+		op1 = (void *)(long)((insn >> 12) & 0xf);
+		break;
+
+	case XFLB:
+		op0 = (void *)(long)((insn >> 17) & 0xff);
+		op1 = (void *)&current->thread.TS_FPR((insn >> 11) & 0x1f);
+		break;
+
+	default:
+		goto illegal;
+	}
+
+	/*
+	 * If we support a HW FPU, we need to ensure the FP state
+	 * is flushed into the thread_struct before attempting
+	 * emulation
+	 */
+	flush_fp_to_thread(current);
+
+	eflag = func(op0, op1, op2, op3);
+
+	if (insn & 1) {
+		regs->ccr &= ~(0x0f000000);
+		regs->ccr |= (__FPU_FPSCR >> 4) & 0x0f000000;
+	}
+
+	trap = record_exception(regs, eflag);
+	if (trap)
+		return 1;
+
+	switch (type) {
+	case DU:
+	case XEU:
+		regs->gpr[idx] = (unsigned long)op1;
+		break;
+
+	default:
+		break;
+	}
+
+	regs_add_return_ip(regs, 4);
+	return 0;
+
+illegal:
+	return -ENOSYS;
+}