From patchwork Thu Apr 3 00:06:22 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Denis Mukhin X-Patchwork-Id: 14036616 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2521FC3601E for ; Thu, 3 Apr 2025 00:06:50 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.936147.1337457 (Exim 4.92) (envelope-from ) id 1u086J-00023P-VY; Thu, 03 Apr 2025 00:06:31 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 936147.1337457; Thu, 03 Apr 2025 00:06:31 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1u086J-00023I-R2; Thu, 03 Apr 2025 00:06:31 +0000 Received: by outflank-mailman (input) for mailman id 936147; Thu, 03 Apr 2025 00:06:30 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1u086I-000234-P9 for xen-devel@lists.xenproject.org; Thu, 03 Apr 2025 00:06:30 +0000 Received: from mail-4316.protonmail.ch (mail-4316.protonmail.ch [185.70.43.16]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 7dba8132-101f-11f0-9ffb-bf95429c2676; Thu, 03 Apr 2025 02:06:29 +0200 (CEST) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 7dba8132-101f-11f0-9ffb-bf95429c2676 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=proton.me; s=loyd6buz5vf63b67ydln5ulsbm.protonmail; t=1743638788; x=1743897988; bh=TBQLnMlSerAh3mR7qO98G0AbutCfSkHB8vVcz9TwNvY=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID:BIMI-Selector:List-Unsubscribe:List-Unsubscribe-Post; b=PppSoZd4UgwV5D/68YhO2Lbx4eJjbIX9gzEMQ4qIb3yfQbGmFCTRKFH8chjItIRmq vGitz+iz9RUM6bPLc/wKjR4P7ISo/NFy9MPefeEi59jkr8J5eiJ/sjAXvR9DLHYvcv qpwHE4Rv3fydF6uWc82lzJPmV7UV3UpY+8ogDuqpl99pKlUYOEy1s2tBbxaUkgOxtP LEHM6riRiQxR/4XPeoRo3Tyd71eoY3Pn6i9dXaYGtehUD32vaju6nKQwIsoq6xm4LP Lmh0X1Lg/YsBwSriH+YDfUVyrZrzqkmqwUb/HiS3I0/WLYJ5LQx3709CQzgjGa2yEh f95i2zubfAUwA== Date: Thu, 03 Apr 2025 00:06:22 +0000 To: xen-devel@lists.xenproject.org From: dmkhn@proton.me Cc: andrew.cooper3@citrix.com, anthony.perard@vates.tech, jbeulich@suse.com, julien@xen.org, michal.orzel@amd.com, roger.pau@citrix.com, sstabellini@kernel.org, dmukhin@ford.com Subject: [PATCH v1 1/3] xen/console: cleanup conring management Message-ID: <20250403000604.169619-2-dmukhin@ford.com> In-Reply-To: <20250403000604.169619-1-dmukhin@ford.com> References: <20250403000604.169619-1-dmukhin@ford.com> Feedback-ID: 123220910:user:proton X-Pm-Message-ID: 4c3ff2d98affcb365872036c446a394a36e85caa MIME-Version: 1.0 From: Denis Mukhin Move console_locks_busted handling inside conring_puts() to remove tasklet code duplication. Signed-off-by: Denis Mukhin --- xen/drivers/char/console.c | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-) diff --git a/xen/drivers/char/console.c b/xen/drivers/char/console.c index c3150fbdb7..aaa97088aa 100644 --- a/xen/drivers/char/console.c +++ b/xen/drivers/char/console.c @@ -325,6 +325,17 @@ static void cf_check do_dec_thresh(unsigned char key, bool unused) * ******************************************************** */ +static void cf_check notify_dom0_con_ring(void *unused) +{ + send_global_virq(VIRQ_CON_RING); +} + +static DECLARE_SOFTIRQ_TASKLET(notify_dom0_con_ring_tasklet, + notify_dom0_con_ring, + NULL); + +static bool console_locks_busted; + static void conring_puts(const char *str, size_t len) { ASSERT(rspin_is_locked(&console_lock)); @@ -334,6 +345,9 @@ static void conring_puts(const char *str, size_t len) if ( conringp - conringc > conring_size ) conringc = conringp - conring_size; + + if ( !console_locks_busted ) + tasklet_schedule(¬ify_dom0_con_ring_tasklet); } long read_console_ring(struct xen_sysctl_readconsole *op) @@ -594,13 +608,6 @@ static void cf_check serial_rx(char c) __serial_rx(c); } -static void cf_check notify_dom0_con_ring(void *unused) -{ - send_global_virq(VIRQ_CON_RING); -} -static DECLARE_SOFTIRQ_TASKLET(notify_dom0_con_ring_tasklet, - notify_dom0_con_ring, NULL); - #ifdef CONFIG_X86 static inline void xen_console_write_debug_port(const char *buf, size_t len) { @@ -648,10 +655,7 @@ static long guest_console_write(XEN_GUEST_HANDLE_PARAM(char) buffer, #endif if ( opt_console_to_ring ) - { conring_puts(kbuf, kcount); - tasklet_schedule(¬ify_dom0_con_ring_tasklet); - } nrspin_unlock_irq(&console_lock); } @@ -753,8 +757,6 @@ long do_console_io( * ***************************************************** */ -static bool console_locks_busted; - static void __putstr(const char *str) { size_t len = strlen(str); @@ -775,9 +777,6 @@ static void __putstr(const char *str) #endif conring_puts(str, len); - - if ( !console_locks_busted ) - tasklet_schedule(¬ify_dom0_con_ring_tasklet); } static int printk_prefix_check(char *p, char **pp) From patchwork Thu Apr 3 00:06:27 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Denis Mukhin X-Patchwork-Id: 14036617 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1335DC369A0 for ; Thu, 3 Apr 2025 00:06:52 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.936148.1337465 (Exim 4.92) (envelope-from ) id 1u086N-0002IY-4Z; Thu, 03 Apr 2025 00:06:35 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 936148.1337465; Thu, 03 Apr 2025 00:06:35 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1u086N-0002IR-1W; 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h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID:BIMI-Selector:List-Unsubscribe:List-Unsubscribe-Post; b=j/stRxmIQoJIllzxWPVBCAYzIBg1i89TD0fYa10MFfZnfrOIqUT0DJ0EbG4fXzbEU +11HUlDCoIv9BVigGf5mAsqEbNs3vsBYTDTmm+TngsTSOC4DsKGhcIW6N/Jehtou54 5c/rSwAn35jU7lStZEjig2WCiXv/7TW4u8UHZLT2GL2a/JTuKfrf0zuO61h+ffzLNd obf95oPi7SweOKbGxDqolF0McnZPwD21Grtmj60TV2/6zMVt6UddZGPo1J3G4eMVIK 8wdZodNGgVro5LrIhUgk1mo6IqchTkf03oiDXBUOIO2XOKA+JtorDVJ2arSAz7USva 4o2ziWGOx12Ig== Date: Thu, 03 Apr 2025 00:06:27 +0000 To: xen-devel@lists.xenproject.org From: dmkhn@proton.me Cc: andrew.cooper3@citrix.com, anthony.perard@vates.tech, jbeulich@suse.com, julien@xen.org, michal.orzel@amd.com, roger.pau@citrix.com, sstabellini@kernel.org, dmukhin@ford.com Subject: [PATCH v1 2/3] xen/console: introduce console_puts() Message-ID: <20250403000604.169619-3-dmukhin@ford.com> In-Reply-To: <20250403000604.169619-1-dmukhin@ford.com> References: <20250403000604.169619-1-dmukhin@ford.com> Feedback-ID: 123220910:user:proton X-Pm-Message-ID: cb58e55f650cb81c34a5b94f37bd90dc617546e1 MIME-Version: 1.0 From: Denis Mukhin guest_console_write() duplicates the code from __putstr(), eliminate code duplication. Introduce console_puts() for writing a buffer to console devices. Also, introduce internal console flags to control which console devices should be used. Signed-off-by: Denis Mukhin --- xen/drivers/char/console.c | 112 ++++++++++++++++++++++--------------- 1 file changed, 66 insertions(+), 46 deletions(-) diff --git a/xen/drivers/char/console.c b/xen/drivers/char/console.c index aaa97088aa..2618c2e47d 100644 --- a/xen/drivers/char/console.c +++ b/xen/drivers/char/console.c @@ -41,6 +41,20 @@ #include #endif +/* Internal console flags. */ +enum { + CONSOLE_SERIAL = BIT(0, U), /* Use serial device. */ + CONSOLE_PV = BIT(1, U), /* Use PV console. */ + CONSOLE_VIDEO = BIT(2, U), /* Use video device. */ + CONSOLE_DEBUG = BIT(3, U), /* Use debug device. */ + CONSOLE_RING = BIT(4, U), /* Use console ring. */ + CONSOLE_DEFAULT = CONSOLE_SERIAL | CONSOLE_PV | CONSOLE_VIDEO | + CONSOLE_DEBUG, + CONSOLE_ALL = CONSOLE_DEFAULT | CONSOLE_RING, +}; + +static void console_puts(const char *str, size_t len, unsigned int flags); + /* console: comma-separated list of console outputs. */ static char __initdata opt_console[30] = OPT_CONSOLE_STR; string_param("console", opt_console); @@ -338,8 +352,6 @@ static bool console_locks_busted; static void conring_puts(const char *str, size_t len) { - ASSERT(rspin_is_locked(&console_lock)); - while ( len-- ) conring[CONRING_IDX_MASK(conringp++)] = *str++; @@ -432,9 +444,6 @@ void console_serial_puts(const char *s, size_t nr) serial_steal_fn(s, nr); else serial_puts(sercon_handle, s, nr); - - /* Copy all serial output into PV console */ - pv_console_puts(s, nr); } static void cf_check dump_console_ring_key(unsigned char key) @@ -468,8 +477,7 @@ static void cf_check dump_console_ring_key(unsigned char key) c += len; } - console_serial_puts(buf, sofar); - video_puts(buf, sofar); + console_puts(buf, sofar, CONSOLE_SERIAL | CONSOLE_VIDEO | CONSOLE_PV); free_xenheap_pages(buf, order); } @@ -618,11 +626,61 @@ static inline void xen_console_write_debug_port(const char *buf, size_t len) } #endif +static inline void console_debug_puts(const char *str, size_t len) +{ +#ifdef CONFIG_X86 + if ( opt_console_xen ) + { + if ( xen_guest ) + xen_hypercall_console_write(str, len); + else + xen_console_write_debug_port(str, len); + } +#endif +} + +/* + * Write buffer to all enabled console devices. + * + * That will handle all possible scenarios working w/ console + * - physical console (serial console, VGA console (x86 only)); + * - PV console; + * - debug console (x86 only): debug I/O port or __HYPERVISOR_console_io + * hypercall; + * - console ring. + */ +static void console_puts(const char *str, size_t len, unsigned int flags) +{ + ASSERT(rspin_is_locked(&console_lock)); + + if ( flags & CONSOLE_SERIAL ) + console_serial_puts(str, len); + + if ( flags & CONSOLE_PV ) + pv_console_puts(str, len); + + if ( flags & CONSOLE_VIDEO ) + video_puts(str, len); + + if ( flags & CONSOLE_DEBUG ) + console_debug_puts(str, len); + + if ( flags & CONSOLE_RING ) + conring_puts(str, len); +} + +static inline void __putstr(const char *str) +{ + console_puts(str, strlen(str), CONSOLE_ALL); +} + static long guest_console_write(XEN_GUEST_HANDLE_PARAM(char) buffer, unsigned int count) { char kbuf[128]; unsigned int kcount = 0; + unsigned int flags = opt_console_to_ring + ? CONSOLE_ALL : CONSOLE_DEFAULT; struct domain *cd = current->domain; while ( count > 0 ) @@ -640,23 +698,7 @@ static long guest_console_write(XEN_GUEST_HANDLE_PARAM(char) buffer, { /* Use direct console output as it could be interactive */ nrspin_lock_irq(&console_lock); - - console_serial_puts(kbuf, kcount); - video_puts(kbuf, kcount); - -#ifdef CONFIG_X86 - if ( opt_console_xen ) - { - if ( xen_guest ) - xen_hypercall_console_write(kbuf, kcount); - else - xen_console_write_debug_port(kbuf, kcount); - } -#endif - - if ( opt_console_to_ring ) - conring_puts(kbuf, kcount); - + console_puts(kbuf, kcount, flags); nrspin_unlock_irq(&console_lock); } else @@ -757,28 +799,6 @@ long do_console_io( * ***************************************************** */ -static void __putstr(const char *str) -{ - size_t len = strlen(str); - - ASSERT(rspin_is_locked(&console_lock)); - - console_serial_puts(str, len); - video_puts(str, len); - -#ifdef CONFIG_X86 - if ( opt_console_xen ) - { - if ( xen_guest ) - xen_hypercall_console_write(str, len); - else - xen_console_write_debug_port(str, len); - } -#endif - - conring_puts(str, len); -} - static int printk_prefix_check(char *p, char **pp) { int loglvl = -1; From patchwork Thu Apr 3 00:06:32 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Denis Mukhin X-Patchwork-Id: 14036618 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9A585C36018 for ; Thu, 3 Apr 2025 00:06:52 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.936150.1337476 (Exim 4.92) (envelope-from ) id 1u086S-0002aq-De; Thu, 03 Apr 2025 00:06:40 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 936150.1337476; Thu, 03 Apr 2025 00:06:40 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1u086S-0002aj-8e; Thu, 03 Apr 2025 00:06:40 +0000 Received: by outflank-mailman (input) for mailman id 936150; Thu, 03 Apr 2025 00:06:39 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1u086R-000234-AB for xen-devel@lists.xenproject.org; Thu, 03 Apr 2025 00:06:39 +0000 Received: from mail-4316.protonmail.ch (mail-4316.protonmail.ch [185.70.43.16]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 830b6832-101f-11f0-9ffb-bf95429c2676; Thu, 03 Apr 2025 02:06:37 +0200 (CEST) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 830b6832-101f-11f0-9ffb-bf95429c2676 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=proton.me; s=lluhb2firrddhpi264e3pc4bsy.protonmail; t=1743638797; x=1743897997; bh=GYrF79Lky+t8pJBLpkLDqHS5mjT9sR3p7CaY+cQEX88=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID:BIMI-Selector:List-Unsubscribe:List-Unsubscribe-Post; b=GjjTpaza1P+1T0MBPu3LhQ4JPYAc/JiUfL5MOerA+xFcmNwv6vGJit7Ht90Kshu/I K3EWULEH/Pz8AaYQAjS3CbXlzavFt5Tbs7ZMFz8aQ7hPSuBcLzyPmo34WFPUxeOZCi Txoy3EEzjK5fGMlwGyc7gTSOSBsj8hwcNJ1nIMueHRWq8OYycYlspL8xCAg6yQMrAV gnp5mtxlebkEZ+/sElzxhJW+TsKkFMlfB1umiEiNlr6hgBGg+VMOhCqdlsv2PMLC7D dc3hguy/FuQ4XnkFitHEOwOrTf7RO0lnHK3MO1wYLIJN4NqoXkPpMIVOj6x6aaa+Ab T8OQvn3y1i2JA== Date: Thu, 03 Apr 2025 00:06:32 +0000 To: xen-devel@lists.xenproject.org From: dmkhn@proton.me Cc: andrew.cooper3@citrix.com, anthony.perard@vates.tech, jbeulich@suse.com, julien@xen.org, michal.orzel@amd.com, roger.pau@citrix.com, sstabellini@kernel.org, dmukhin@ford.com Subject: [PATCH v1 3/3] xen/console: introduce conring_flush() Message-ID: <20250403000604.169619-4-dmukhin@ford.com> In-Reply-To: <20250403000604.169619-1-dmukhin@ford.com> References: <20250403000604.169619-1-dmukhin@ford.com> Feedback-ID: 123220910:user:proton X-Pm-Message-ID: 9f9887882ae5bbc02fc76b68206c9230209cbb57 MIME-Version: 1.0 From: Denis Mukhin Introduce conring_flush() to ensure all messages kept in the internal console ring are sent to all physical consoles (serial, VGA (x86)) after their initialization is completed. Resolves: https://gitlab.com/xen-project/xen/-/issues/184 Signed-off-by: Denis Mukhin --- The patch conflicts with https://lore.kernel.org/xen-devel/20250331230508.440198-7-dmukhin@ford.com/ in console_init_preirq() --- xen/drivers/char/console.c | 34 ++++++++++++++++++++++++---------- 1 file changed, 24 insertions(+), 10 deletions(-) diff --git a/xen/drivers/char/console.c b/xen/drivers/char/console.c index 2618c2e47d..18eb66df89 100644 --- a/xen/drivers/char/console.c +++ b/xen/drivers/char/console.c @@ -446,24 +446,22 @@ void console_serial_puts(const char *s, size_t nr) serial_puts(sercon_handle, s, nr); } -static void cf_check dump_console_ring_key(unsigned char key) +/* + * Flush contents of the conring to the physical console devices. + */ +static int conring_flush(void) { uint32_t idx, len, sofar, c; unsigned int order; char *buf; + unsigned long flags; - printk("'%c' pressed -> dumping console ring buffer (dmesg)\n", key); - - /* create a buffer in which we'll copy the ring in the correct - order and NUL terminate */ order = get_order_from_bytes(conring_size + 1); buf = alloc_xenheap_pages(order, 0); if ( buf == NULL ) - { - printk("unable to allocate memory!\n"); - return; - } + return -ENOMEM; + flags = console_lock_recursive_irqsave(); c = conringc; sofar = 0; while ( (c != conringp) ) @@ -478,8 +476,21 @@ static void cf_check dump_console_ring_key(unsigned char key) } console_puts(buf, sofar, CONSOLE_SERIAL | CONSOLE_VIDEO | CONSOLE_PV); + console_unlock_recursive_irqrestore(flags); free_xenheap_pages(buf, order); + + return 0; +} + +static void cf_check conring_dump_keyhandler(unsigned char key) +{ + int rc; + + printk("'%c' pressed -> dumping console ring buffer (dmesg)\n", key); + rc = conring_flush(); + if ( rc ) + printk("failed to dump console ring buffer: %d\n", rc); } /* @@ -1044,6 +1055,9 @@ void __init console_init_preirq(void) serial_set_rx_handler(sercon_handle, serial_rx); pv_console_set_rx_handler(serial_rx); + /* NB: send conring contents to all enabled physical consoles, if any */ + conring_flush(); + /* HELLO WORLD --- start-of-day banner text. */ nrspin_lock(&console_lock); __putstr(xen_banner()); @@ -1134,7 +1148,7 @@ void __init console_endboot(void) if ( opt_conswitch[1] == 'x' ) console_rx = max_console_rx; - register_keyhandler('w', dump_console_ring_key, + register_keyhandler('w', conring_dump_keyhandler, "synchronously dump console ring buffer (dmesg)", 0); register_irq_keyhandler('+', &do_inc_thresh, "increase log level threshold", 0);