From e90a21ea801d1776d9a786ad02354fd3fe23ce09 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Thu, 20 May 2021 13:50:44 +0000 Subject: [PATCH] powerpc/lib/code-patching: Don't use struct 'ppc_inst' for runnable code in tests. 'struct ppc_inst' is meant to represent an instruction internally, it is not meant to dereference code in memory. For testing code patching, use patch_instruction() to properly write into memory the code to be tested. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/d8425fb42a4adebc35b7509f121817eeb02fac31.1621516826.git.christophe.leroy@csgroup.eu --- arch/powerpc/lib/code-patching.c | 95 ++++++++++++++++++-------------- 1 file changed, 53 insertions(+), 42 deletions(-) diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c index 82f2c1edb498..60201cb6f3a1 100644 --- a/arch/powerpc/lib/code-patching.c +++ b/arch/powerpc/lib/code-patching.c @@ -422,9 +422,9 @@ static void __init test_branch_iform(void) { int err; struct ppc_inst instr; - unsigned long addr; - - addr = (unsigned long)&instr; + u32 tmp[2]; + struct ppc_inst *iptr = (struct ppc_inst *)tmp; + unsigned long addr = (unsigned long)tmp; /* The simplest case, branch to self, no flags */ check(instr_is_branch_iform(ppc_inst(0x48000000))); @@ -445,52 +445,57 @@ static void __init test_branch_iform(void) check(!instr_is_branch_iform(ppc_inst(0x7bfffffd))); /* Absolute branch to 0x100 */ - instr = ppc_inst(0x48000103); - check(instr_is_branch_to_addr(&instr, 0x100)); + patch_instruction(iptr, ppc_inst(0x48000103)); + check(instr_is_branch_to_addr(iptr, 0x100)); /* Absolute branch to 0x420fc */ - instr = ppc_inst(0x480420ff); - check(instr_is_branch_to_addr(&instr, 0x420fc)); + patch_instruction(iptr, ppc_inst(0x480420ff)); + check(instr_is_branch_to_addr(iptr, 0x420fc)); /* Maximum positive relative branch, + 20MB - 4B */ - instr = ppc_inst(0x49fffffc); - check(instr_is_branch_to_addr(&instr, addr + 0x1FFFFFC)); + patch_instruction(iptr, ppc_inst(0x49fffffc)); + check(instr_is_branch_to_addr(iptr, addr + 0x1FFFFFC)); /* Smallest negative relative branch, - 4B */ - instr = ppc_inst(0x4bfffffc); - check(instr_is_branch_to_addr(&instr, addr - 4)); + patch_instruction(iptr, ppc_inst(0x4bfffffc)); + check(instr_is_branch_to_addr(iptr, addr - 4)); /* Largest negative relative branch, - 32 MB */ - instr = ppc_inst(0x4a000000); - check(instr_is_branch_to_addr(&instr, addr - 0x2000000)); + patch_instruction(iptr, ppc_inst(0x4a000000)); + check(instr_is_branch_to_addr(iptr, addr - 0x2000000)); /* Branch to self, with link */ - err = create_branch(&instr, &instr, addr, BRANCH_SET_LINK); - check(instr_is_branch_to_addr(&instr, addr)); + err = create_branch(&instr, iptr, addr, BRANCH_SET_LINK); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr)); /* Branch to self - 0x100, with link */ - err = create_branch(&instr, &instr, addr - 0x100, BRANCH_SET_LINK); - check(instr_is_branch_to_addr(&instr, addr - 0x100)); + err = create_branch(&instr, iptr, addr - 0x100, BRANCH_SET_LINK); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr - 0x100)); /* Branch to self + 0x100, no link */ - err = create_branch(&instr, &instr, addr + 0x100, 0); - check(instr_is_branch_to_addr(&instr, addr + 0x100)); + err = create_branch(&instr, iptr, addr + 0x100, 0); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr + 0x100)); /* Maximum relative negative offset, - 32 MB */ - err = create_branch(&instr, &instr, addr - 0x2000000, BRANCH_SET_LINK); - check(instr_is_branch_to_addr(&instr, addr - 0x2000000)); + err = create_branch(&instr, iptr, addr - 0x2000000, BRANCH_SET_LINK); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr - 0x2000000)); /* Out of range relative negative offset, - 32 MB + 4*/ - err = create_branch(&instr, &instr, addr - 0x2000004, BRANCH_SET_LINK); + err = create_branch(&instr, iptr, addr - 0x2000004, BRANCH_SET_LINK); check(err); /* Out of range relative positive offset, + 32 MB */ - err = create_branch(&instr, &instr, addr + 0x2000000, BRANCH_SET_LINK); + err = create_branch(&instr, iptr, addr + 0x2000000, BRANCH_SET_LINK); check(err); /* Unaligned target */ - err = create_branch(&instr, &instr, addr + 3, BRANCH_SET_LINK); + err = create_branch(&instr, iptr, addr + 3, BRANCH_SET_LINK); check(err); /* Check flags are masked correctly */ - err = create_branch(&instr, &instr, addr, 0xFFFFFFFC); - check(instr_is_branch_to_addr(&instr, addr)); + err = create_branch(&instr, iptr, addr, 0xFFFFFFFC); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr)); check(ppc_inst_equal(instr, ppc_inst(0x48000000))); } @@ -513,9 +518,10 @@ static void __init test_branch_bform(void) int err; unsigned long addr; struct ppc_inst *iptr, instr; + u32 tmp[2]; unsigned int flags; - iptr = &instr; + iptr = (struct ppc_inst *)tmp; addr = (unsigned long)iptr; /* The simplest case, branch to self, no flags */ @@ -528,39 +534,43 @@ static void __init test_branch_bform(void) check(!instr_is_branch_bform(ppc_inst(0x7bffffff))); /* Absolute conditional branch to 0x100 */ - instr = ppc_inst(0x43ff0103); - check(instr_is_branch_to_addr(&instr, 0x100)); + patch_instruction(iptr, ppc_inst(0x43ff0103)); + check(instr_is_branch_to_addr(iptr, 0x100)); /* Absolute conditional branch to 0x20fc */ - instr = ppc_inst(0x43ff20ff); - check(instr_is_branch_to_addr(&instr, 0x20fc)); + patch_instruction(iptr, ppc_inst(0x43ff20ff)); + check(instr_is_branch_to_addr(iptr, 0x20fc)); /* Maximum positive relative conditional branch, + 32 KB - 4B */ - instr = ppc_inst(0x43ff7ffc); - check(instr_is_branch_to_addr(&instr, addr + 0x7FFC)); + patch_instruction(iptr, ppc_inst(0x43ff7ffc)); + check(instr_is_branch_to_addr(iptr, addr + 0x7FFC)); /* Smallest negative relative conditional branch, - 4B */ - instr = ppc_inst(0x43fffffc); - check(instr_is_branch_to_addr(&instr, addr - 4)); + patch_instruction(iptr, ppc_inst(0x43fffffc)); + check(instr_is_branch_to_addr(iptr, addr - 4)); /* Largest negative relative conditional branch, - 32 KB */ - instr = ppc_inst(0x43ff8000); - check(instr_is_branch_to_addr(&instr, addr - 0x8000)); + patch_instruction(iptr, ppc_inst(0x43ff8000)); + check(instr_is_branch_to_addr(iptr, addr - 0x8000)); /* All condition code bits set & link */ flags = 0x3ff000 | BRANCH_SET_LINK; /* Branch to self */ err = create_cond_branch(&instr, iptr, addr, flags); - check(instr_is_branch_to_addr(&instr, addr)); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr)); /* Branch to self - 0x100 */ err = create_cond_branch(&instr, iptr, addr - 0x100, flags); - check(instr_is_branch_to_addr(&instr, addr - 0x100)); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr - 0x100)); /* Branch to self + 0x100 */ err = create_cond_branch(&instr, iptr, addr + 0x100, flags); - check(instr_is_branch_to_addr(&instr, addr + 0x100)); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr + 0x100)); /* Maximum relative negative offset, - 32 KB */ err = create_cond_branch(&instr, iptr, addr - 0x8000, flags); - check(instr_is_branch_to_addr(&instr, addr - 0x8000)); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr - 0x8000)); /* Out of range relative negative offset, - 32 KB + 4*/ err = create_cond_branch(&instr, iptr, addr - 0x8004, flags); @@ -576,7 +586,8 @@ static void __init test_branch_bform(void) /* Check flags are masked correctly */ err = create_cond_branch(&instr, iptr, addr, 0xFFFFFFFC); - check(instr_is_branch_to_addr(&instr, addr)); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr)); check(ppc_inst_equal(instr, ppc_inst(0x43FF0000))); }