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Date:   Thu, 20 Oct 2022 12:49:45 +0300
From:   Alexey Dobriyan <adobriyan@gmail.com>
To:     akpm@linux-foundation.org, linux-kernel@vger.kernel.org
Cc:     mm-commits@vger.kernel.org, torvalds@linux-foundation.org,
        masahiroy@kernel.org, keescook@chromium.org,
        gregkh@linuxfoundation.org, andriy.shevchenko@linux.intel.com,
        Jason@zx2c4.com, akpm@linux-foundation.org
Subject: [PATCH -mm] -funsigned-char, x86: make struct p4_event_bind::cntr
 signed array
Message-ID: <Y1EZuQcO8UoN91cX@localhost.localdomain>
References: <20221020000356.177CDC433C1@smtp.kernel.org>
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struct p4_event_bind::cntr[][] should be signed because of
the following code:

	int i, j;
        for (i = 0; i < P4_CNTR_LIMIT; i++) {
          ===>  j = bind->cntr[thread][i];
                if (j != -1 && !test_bit(j, used_mask))
                        return j;
        }

Making this member unsigned will make "j" 255 and fail "j != -1"
comparison.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
---

 arch/x86/events/intel/p4.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/events/intel/p4.c
+++ b/arch/x86/events/intel/p4.c
@@ -24,7 +24,7 @@ struct p4_event_bind {
 	unsigned int escr_msr[2];		/* ESCR MSR for this event */
 	unsigned int escr_emask;		/* valid ESCR EventMask bits */
 	unsigned int shared;			/* event is shared across threads */
-	char cntr[2][P4_CNTR_LIMIT];		/* counter index (offset), -1 on absence */
+	signed char cntr[2][P4_CNTR_LIMIT];	/* counter index (offset), -1 on absence */
 };
 
 struct p4_pebs_bind {