On Fri, 2024-03-15 at 07:14 +0000, Christophe Leroy wrote:
>
>
> Le 15/03/2024 à 03:57, Benjamin Gray a écrit :
> > patch_instructions() introduces new behaviour with a couple of
> > variations. Test each case of
> >
> > * a repeated 32-bit instruction,
> > * a repeated 64-bit instruction (ppc64), and
> > * a copied sequence of instructions
> >
> > for both on a single page and when it crosses a page boundary.
> >
> > Signed-off-by: Benjamin Gray <bg...@linux.ibm.com>
> > ---
> > arch/powerpc/lib/test-code-patching.c | 92
> > +++++++++++++++++++++++++++
> > 1 file changed, 92 insertions(+)
> >
> > diff --git a/arch/powerpc/lib/test-code-patching.c
> > b/arch/powerpc/lib/test-code-patching.c
> > index c44823292f73..35a3756272df 100644
> > --- a/arch/powerpc/lib/test-code-patching.c
> > +++ b/arch/powerpc/lib/test-code-patching.c
> > @@ -347,6 +347,97 @@ static void __init
> > test_prefixed_patching(void)
> > check(!memcmp(iptr, expected, sizeof(expected)));
> > }
> >
> > +static void __init test_multi_instruction_patching(void)
> > +{
> > + u32 code[256];
>
> Build failure:
>
> CC arch/powerpc/lib/test-code-patching.o
> arch/powerpc/lib/test-code-patching.c: In function
> 'test_multi_instruction_patching':
> arch/powerpc/lib/test-code-patching.c:439:1: error: the frame size of
> 1040 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
> 439 | }
> | ^
> cc1: all warnings being treated as errors
> make[4]: *** [scripts/Makefile.build:243:
> arch/powerpc/lib/test-code-patching.o] Error 1
>
>
> I have to avoid big arrays on the stack.
All good, I can do that.
I do run my patches through a couple of 32-bit configs, but I didn't
see this error. Is this a standard config I should be testing with?
>
>
> > + void *buf;
> > + u32 *addr32;
> > + u64 *addr64;
> > + ppc_inst_t inst64 = ppc_inst_prefix(OP_PREFIX << 26 | 3UL
> > << 24, PPC_RAW_TRAP());
> > + u32 inst32 = PPC_RAW_NOP();
> > +
> > + buf = vzalloc(PAGE_SIZE * 8);
> > + check(buf);
> > + if (!buf)
> > + return;
> > +
> > + /* Test single page 32-bit repeated instruction */
> > + addr32 = buf + PAGE_SIZE;
> > + check(!patch_instructions(addr32 + 1, &inst32, 12, true));
> > +
> > + check(addr32[0] == 0);
> > + check(addr32[1] == inst32);
> > + check(addr32[2] == inst32);
> > + check(addr32[3] == inst32);
> > + check(addr32[4] == 0);
> > +
> > + /* Test single page 64-bit repeated instruction */
> > + if (IS_ENABLED(CONFIG_PPC64)) {
> > + check(ppc_inst_prefixed(inst64));
> > +
> > + addr64 = buf + PAGE_SIZE * 2;
> > + ppc_inst_write(code, inst64);
> > + check(!patch_instructions((u32 *)(addr64 + 1),
> > code, 24, true));
> > +
> > + check(addr64[0] == 0);
> > + check(ppc_inst_equal(ppc_inst_read((u32
> > *)&addr64[1]), inst64));
> > + check(ppc_inst_equal(ppc_inst_read((u32
> > *)&addr64[2]), inst64));
> > + check(ppc_inst_equal(ppc_inst_read((u32
> > *)&addr64[3]), inst64));
> > + check(addr64[4] == 0);
> > + }
> > +
> > + /* Test single page memcpy */
> > + addr32 = buf + PAGE_SIZE * 3;
> > +
> > + for (int i = 0; i < ARRAY_SIZE(code); i++)
> > + code[i] = i + 1;
> > +
> > + check(!patch_instructions(addr32 + 1, code, sizeof(code),
> > false));
> > +
> > + check(addr32[0] == 0);
> > + check(!memcmp(&addr32[1], code, sizeof(code)));
> > + check(addr32[ARRAY_SIZE(code) + 1] == 0);
> > +
> > + /* Test multipage 32-bit repeated instruction */
> > + addr32 = buf + PAGE_SIZE * 4 - 8;
> > + check(!patch_instructions(addr32 + 1, &inst32, 12, true));
> > +
> > + check(addr32[0] == 0);
> > + check(addr32[1] == inst32);
> > + check(addr32[2] == inst32);
> > + check(addr32[3] == inst32);
> > + check(addr32[4] == 0);
> > +
> > + /* Test multipage 64-bit repeated instruction */
> > + if (IS_ENABLED(CONFIG_PPC64)) {
> > + check(ppc_inst_prefixed(inst64));
> > +
> > + addr64 = buf + PAGE_SIZE * 5 - 8;
> > + ppc_inst_write(code, inst64);
> > + check(!patch_instructions((u32 *)(addr64 + 1),
> > code, 24, true));
> > +
> > + check(addr64[0] == 0);
> > + check(ppc_inst_equal(ppc_inst_read((u32
> > *)&addr64[1]), inst64));
> > + check(ppc_inst_equal(ppc_inst_read((u32
> > *)&addr64[2]), inst64));
> > + check(ppc_inst_equal(ppc_inst_read((u32
> > *)&addr64[3]), inst64));
> > + check(addr64[4] == 0);
> > + }
> > +
> > + /* Test multipage memcpy */
> > + addr32 = buf + PAGE_SIZE * 6 - 12;
> > +
> > + for (int i = 0; i < ARRAY_SIZE(code); i++)
> > + code[i] = i + 1;
> > +
> > + check(!patch_instructions(addr32 + 1, code, sizeof(code),
> > false));
> > +
> > + check(addr32[0] == 0);
> > + check(!memcmp(&addr32[1], code, sizeof(code)));
> > + check(addr32[ARRAY_SIZE(code) + 1] == 0);
> > +
> > + vfree(buf);
> > +}
> > +
> > static int __init test_code_patching(void)
> > {
> > pr_info("Running code patching self-tests ...\n");
> > @@ -356,6 +447,7 @@ static int __init test_code_patching(void)
> > test_create_function_call();
> > test_translate_branch();
> > test_prefixed_patching();
> > + test_multi_instruction_patching();
> >
> > return 0;
> > }
