The following commit has been merged into the x86/cpu branch of tip:
Commit-ID: a866a6775793a2554585073704b83c4691d80740
Gitweb: https://git.kernel.org/tip/a866a6775793a2554585073704b83c4691d80740
Author: Ahmed S. Darwish <darwi@linutronix.de>
AuthorDate: Mon, 24 Mar 2025 15:20:23 +01:00
Committer: Ingo Molnar <mingo@kernel.org>
CommitterDate: Tue, 25 Mar 2025 09:53:44 +01:00
tools/x86/kcpuid: Exit the program on invalid parameters
If the user passed an invalid CPUID index value through --leaf=index,
kcpuid prints a warning, does nothing, then exits successfully.
Transform the warning to an error, and exit the program with a proper
error code.
Similarly, if the user passed an invalid subleaf, kcpuid prints a
warning, dumps the whole leaf, then exits successfully. Print a clear
error message regarding the invalid subleaf and exit the program with the
proper error code.
Note, moving the "Invalid input index" message from index_to_func() to
show_info() localizes error message handling to the latter, where it
should be. It also allows index_to_func() to be refactored at further
commits.
Note, since after this commit and its parent kcpuid does not just "move
on" on failures, remove the NULL parameter check plus silent exit at
show_func() and show_leaf().
Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20250324142042.29010-3-darwi@linutronix.de
---
tools/arch/x86/kcpuid/kcpuid.c | 22 ++++++++--------------
1 file changed, 8 insertions(+), 14 deletions(-)
diff --git a/tools/arch/x86/kcpuid/kcpuid.c b/tools/arch/x86/kcpuid/kcpuid.c
index 40a9e59..25b10fe 100644
--- a/tools/arch/x86/kcpuid/kcpuid.c
+++ b/tools/arch/x86/kcpuid/kcpuid.c
@@ -481,9 +481,6 @@ static void decode_bits(u32 value, struct reg_desc *rdesc, enum cpuid_reg reg)
static void show_leaf(struct subleaf *leaf)
{
- if (!leaf)
- return;
-
if (show_raw) {
leaf_print_raw(leaf);
} else {
@@ -505,9 +502,6 @@ static void show_func(struct cpuid_func *func)
{
int i;
- if (!func)
- return;
-
for (i = 0; i < func->nr; i++)
show_leaf(&func->leafs[i]);
}
@@ -528,10 +522,9 @@ static inline struct cpuid_func *index_to_func(u32 index)
range = (index & 0x80000000) ? leafs_ext : leafs_basic;
func_idx = index & 0xffff;
- if ((func_idx + 1) > (u32)range->nr) {
- warnx("Invalid input index (0x%x)", index);
+ if ((func_idx + 1) > (u32)range->nr)
return NULL;
- }
+
return &range->funcs[func_idx];
}
@@ -550,18 +543,19 @@ static void show_info(void)
/* Only show specific leaf/subleaf info */
func = index_to_func(user_index);
if (!func)
- return;
+ errx(EXIT_FAILURE, "Invalid input leaf (0x%x)", user_index);
/* Dump the raw data also */
show_raw = true;
if (user_sub != 0xFFFFFFFF) {
- if (user_sub + 1 <= (u32)func->nr) {
- show_leaf(&func->leafs[user_sub]);
- return;
+ if (user_sub + 1 > (u32)func->nr) {
+ errx(EXIT_FAILURE, "Leaf 0x%x has no valid subleaf = 0x%x",
+ user_index, user_sub);
}
- warnx("Invalid input subleaf (0x%x)", user_sub);
+ show_leaf(&func->leafs[user_sub]);
+ return;
}
show_func(func);