[PATCH] x86/fpu/xstate: Fix XSTATE_WARN_ON() to emit relevant diagnostics
From: Andrew Cooper
Date: Wed Aug 10 2022 - 18:19:38 EST
"XSAVE consistency problem" has been reported under Xen, but that's the extent
of my divination skills.
Modify XSTATE_WARN_ON() to force the caller to provide relevant diagnostic
information, and modify each caller suitably.
For check_xstate_against_struct(), this removes a double WARN() where one will
do perfectly fine.
Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
CC: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CC: Ingo Molnar <mingo@xxxxxxxxxx>
CC: Borislav Petkov <bp@xxxxxxxxx>
CC: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
CC: x86@xxxxxxxxxx
CC: Marek Marczykowski-Górecki <marmarek@xxxxxxxxxxxxxxxxxxxxxx>
RFC: CC stable? This has been wonky debugging for 7 years.
Apparently "size 832 != kernel_size 0" so let the debugging continue...
---
arch/x86/kernel/fpu/xstate.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index c8340156bfd2..28b6478ea531 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -440,8 +440,8 @@ static void __init __xstate_dump_leaves(void)
}
}
-#define XSTATE_WARN_ON(x) do { \
- if (WARN_ONCE(x, "XSAVE consistency problem, dumping leaves")) { \
+#define XSTATE_WARN_ON(x, fmt, ...) do { \
+ if (WARN_ONCE(x, "XSAVE consistency problem: " fmt, ##__VA_ARGS__)) { \
__xstate_dump_leaves(); \
} \
} while (0)
@@ -554,8 +554,7 @@ static bool __init check_xstate_against_struct(int nr)
(nr >= XFEATURE_MAX) ||
(nr == XFEATURE_PT_UNIMPLEMENTED_SO_FAR) ||
((nr >= XFEATURE_RSRVD_COMP_11) && (nr <= XFEATURE_RSRVD_COMP_16))) {
- WARN_ONCE(1, "no structure for xstate: %d\n", nr);
- XSTATE_WARN_ON(1);
+ XSTATE_WARN_ON(1, "No structure for xstate: %d\n", nr);
return false;
}
return true;
@@ -598,12 +597,13 @@ static bool __init paranoid_xstate_size_valid(unsigned int kernel_size)
* XSAVES.
*/
if (!xsaves && xfeature_is_supervisor(i)) {
- XSTATE_WARN_ON(1);
+ XSTATE_WARN_ON(1, "Got supervisor feature %d, but XSAVES not advertised\n", i);
return false;
}
}
size = xstate_calculate_size(fpu_kernel_cfg.max_features, compacted);
- XSTATE_WARN_ON(size != kernel_size);
+ XSTATE_WARN_ON(size != kernel_size,
+ "size %u != kernel_size %u\n", size, kernel_size);
return size == kernel_size;
}
--
2.11.0