[PATCH 5.7 117/244] copy_xstate_to_kernel: Fix typo which caused GDB regression

From: Greg Kroah-Hartman
Date: Mon Jul 20 2020 - 12:20:15 EST


From: Kevin Buettner <kevinb@xxxxxxxxxx>

commit 5714ee50bb4375bd586858ad800b1d9772847452 upstream.

This fixes a regression encountered while running the
gdb.base/corefile.exp test in GDB's test suite.

In my testing, the typo prevented the sw_reserved field of struct
fxregs_state from being output to the kernel XSAVES area. Thus the
correct mask corresponding to XCR0 was not present in the core file for
GDB to interrogate, resulting in the following behavior:

[kev@f32-1 gdb]$ ./gdb -q testsuite/outputs/gdb.base/corefile/corefile testsuite/outputs/gdb.base/corefile/corefile.core
Reading symbols from testsuite/outputs/gdb.base/corefile/corefile...
[New LWP 232880]

warning: Unexpected size of section `.reg-xstate/232880' in core file.

With the typo fixed, the test works again as expected.

Signed-off-by: Kevin Buettner <kevinb@xxxxxxxxxx>
Fixes: 9e4636545933 ("copy_xstate_to_kernel(): don't leave parts of destination uninitialized")
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Dave Airlie <airlied@xxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/x86/kernel/fpu/xstate.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -1022,7 +1022,7 @@ int copy_xstate_to_kernel(void *kbuf, st
copy_part(offsetof(struct fxregs_state, st_space), 128,
&xsave->i387.st_space, &kbuf, &offset_start, &count);
if (header.xfeatures & XFEATURE_MASK_SSE)
- copy_part(xstate_offsets[XFEATURE_MASK_SSE], 256,
+ copy_part(xstate_offsets[XFEATURE_SSE], 256,
&xsave->i387.xmm_space, &kbuf, &offset_start, &count);
/*
* Fill xsave->i387.sw_reserved value for ptrace frame: