From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C3A57342519; Tue, 16 Dec 2025 11:35:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765884925; cv=none; b=Fh7ZuZGYiKcqJkwN4J+bLr+sKwOaC7HXoSs+L4klVtdOPiQNz65dMRMXgr6E+KzMNI0xnNZUIflRMvBR0UyqWAx/yvRrNGqGRR60u6uzlqsWv+SKweQBgnijTDbOfrJz91Xn0aAGs85bMXF/rP2Bi3Cb0rU9y+M4fvNTtfT1KWc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765884925; c=relaxed/simple; bh=2RpTc+Ob8oPY4kEEz4C8TWKR9oJAjvCsUxGWO5C3rko=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=heFuts+hB3FXNAoh3AfrCIRrQdSn0lVfofAqS0M8cc2odHtw7kRikuKK2ILwatqjLY2C4BLcd6vBNGkN8G+SltzCwFJFB1ZTteSuN7T//MMNa3eiTsXwyY2+A7CKPoPUs+R4JOkLOO4xEy9yoWdl0RCGdd9MF6brgsDrR62jG9Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zn/9p+8U; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="zn/9p+8U" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3239FC4CEF1; Tue, 16 Dec 2025 11:35:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1765884925; bh=2RpTc+Ob8oPY4kEEz4C8TWKR9oJAjvCsUxGWO5C3rko=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zn/9p+8UsRtNHnbk4ig5wzcvssU1bqLcPdKwImi/K1voXBjgsSUYRjRkoBlxDZbJ/ cTfAgXRWu7tFxdTQmGNx1f2VjDY56ElupoVIPy89RqpRVc5CSmzEKQr3U32rYLnLW9 0Me7+4MKDCwpb8ox58LvB2eslpuV3TuiSKdOzTzI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jonathan Cameron , Mauro Carvalho Chehab , "Borislav Petkov (AMD)" , Ard Biesheuvel , Sasha Levin Subject: [PATCH 6.12 340/354] efi/cper: Add a new helper function to print bitmasks Date: Tue, 16 Dec 2025 12:15:07 +0100 Message-ID: <20251216111333.224707200@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251216111320.896758933@linuxfoundation.org> References: <20251216111320.896758933@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mauro Carvalho Chehab [ Upstream commit a976d790f49499ccaa0f991788ad8ebf92e7fd5c ] Add a helper function to print a string with names associated to each bit field. A typical example is: const char * const bits[] = { "bit 3 name", "bit 4 name", "bit 5 name", }; char str[120]; unsigned int bitmask = BIT(3) | BIT(5); #define MASK GENMASK(5,3) cper_bits_to_str(str, sizeof(str), FIELD_GET(MASK, bitmask), bits, ARRAY_SIZE(bits)); The above code fills string "str" with "bit 3 name|bit 5 name". Reviewed-by: Jonathan Cameron Signed-off-by: Mauro Carvalho Chehab Acked-by: Borislav Petkov (AMD) Signed-off-by: Ard Biesheuvel Signed-off-by: Sasha Levin --- drivers/firmware/efi/cper.c | 60 +++++++++++++++++++++++++++++++++++++ include/linux/cper.h | 2 ++ 2 files changed, 62 insertions(+) diff --git a/drivers/firmware/efi/cper.c b/drivers/firmware/efi/cper.c index b69e68ef3f02b..7f89a9fb2ecad 100644 --- a/drivers/firmware/efi/cper.c +++ b/drivers/firmware/efi/cper.c @@ -12,6 +12,7 @@ * Specification version 2.4. */ +#include #include #include #include @@ -106,6 +107,65 @@ void cper_print_bits(const char *pfx, unsigned int bits, printk("%s\n", buf); } +/** + * cper_bits_to_str - return a string for set bits + * @buf: buffer to store the output string + * @buf_size: size of the output string buffer + * @bits: bit mask + * @strs: string array, indexed by bit position + * @strs_size: size of the string array: @strs + * + * Add to @buf the bitmask in hexadecimal. Then, for each set bit in @bits, + * add the corresponding string describing the bit in @strs to @buf. + * + * A typical example is:: + * + * const char * const bits[] = { + * "bit 3 name", + * "bit 4 name", + * "bit 5 name", + * }; + * char str[120]; + * unsigned int bitmask = BIT(3) | BIT(5); + * #define MASK GENMASK(5,3) + * + * cper_bits_to_str(str, sizeof(str), FIELD_GET(MASK, bitmask), + * bits, ARRAY_SIZE(bits)); + * + * The above code fills the string ``str`` with ``bit 3 name|bit 5 name``. + * + * Return: number of bytes stored or an error code if lower than zero. + */ +int cper_bits_to_str(char *buf, int buf_size, unsigned long bits, + const char * const strs[], unsigned int strs_size) +{ + int len = buf_size; + char *str = buf; + int i, size; + + *buf = '\0'; + + for_each_set_bit(i, &bits, strs_size) { + if (!(bits & BIT_ULL(i))) + continue; + + if (*buf && len > 0) { + *str = '|'; + len--; + str++; + } + + size = strscpy(str, strs[i], len); + if (size < 0) + return size; + + len -= size; + str += size; + } + return len - buf_size; +} +EXPORT_SYMBOL_GPL(cper_bits_to_str); + static const char * const proc_type_strs[] = { "IA32/X64", "IA64", diff --git a/include/linux/cper.h b/include/linux/cper.h index 265b0f8fc0b3c..25858a7608b7d 100644 --- a/include/linux/cper.h +++ b/include/linux/cper.h @@ -584,6 +584,8 @@ const char *cper_mem_err_type_str(unsigned int); const char *cper_mem_err_status_str(u64 status); void cper_print_bits(const char *prefix, unsigned int bits, const char * const strs[], unsigned int strs_size); +int cper_bits_to_str(char *buf, int buf_size, unsigned long bits, + const char * const strs[], unsigned int strs_size); void cper_mem_err_pack(const struct cper_sec_mem_err *, struct cper_mem_err_compact *); const char *cper_mem_err_unpack(struct trace_seq *, -- 2.51.0