From 27d3313807296c3943a96ceef8c2b7279cb56962 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 18 May 2024 19:39:59 +0200 Subject: Adding debian version 6.7.7-1. Signed-off-by: Daniel Baumann --- ...n-Add-emit-function-and-callback-function.patch | 262 --------------------- 1 file changed, 262 deletions(-) delete mode 100644 debian/patches-rt/0081-printk-nbcon-Add-emit-function-and-callback-function.patch (limited to 'debian/patches-rt/0081-printk-nbcon-Add-emit-function-and-callback-function.patch') diff --git a/debian/patches-rt/0081-printk-nbcon-Add-emit-function-and-callback-function.patch b/debian/patches-rt/0081-printk-nbcon-Add-emit-function-and-callback-function.patch deleted file mode 100644 index ab32a05b19..0000000000 --- a/debian/patches-rt/0081-printk-nbcon-Add-emit-function-and-callback-function.patch +++ /dev/null @@ -1,262 +0,0 @@ -From: Thomas Gleixner -Date: Sat, 16 Sep 2023 21:26:06 +0206 -Subject: [PATCH 081/134] printk: nbcon: Add emit function and callback - function for atomic printing -Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.6/older/patches-6.6.7-rt18.tar.xz - -Implement an emit function for nbcon consoles to output printk -messages. It utilizes the lockless printk_get_next_message() and -console_prepend_dropped() functions to retrieve/build the output -message. The emit function includes the required safety points to -check for handover/takeover and calls a new write_atomic callback -of the console driver to output the message. It also includes -proper handling for updating the nbcon console sequence number. - -A new nbcon_write_context struct is introduced. This is provided -to the write_atomic callback and includes only the information -necessary for performing atomic writes. - -Co-developed-by: John Ogness -Signed-off-by: John Ogness -Signed-off-by: Thomas Gleixner (Intel) -Reviewed-by: Petr Mladek -Signed-off-by: Petr Mladek -Link: https://lore.kernel.org/r/20230916192007.608398-8-john.ogness@linutronix.de -Signed-off-by: Sebastian Andrzej Siewior ---- - include/linux/console.h | 21 +++++++++ - kernel/printk/internal.h | 6 ++ - kernel/printk/nbcon.c | 106 ++++++++++++++++++++++++++++++++++++++++++++++- - kernel/printk/printk.c | 9 +-- - 4 files changed, 134 insertions(+), 8 deletions(-) - ---- a/include/linux/console.h -+++ b/include/linux/console.h -@@ -242,6 +242,7 @@ struct printk_buffers; - * be used only with NBCON_PRIO_PANIC @prio. It - * might cause a system freeze when the console - * is used later. -+ * @backlog: Ringbuffer has pending records - * @pbufs: Pointer to the text buffer for this context - * @seq: The sequence number to print for this context - */ -@@ -252,12 +253,29 @@ struct nbcon_context { - enum nbcon_prio prio; - unsigned int allow_unsafe_takeover : 1; - -+ /* members set by emit */ -+ unsigned int backlog : 1; -+ - /* members set by acquire */ - struct printk_buffers *pbufs; - u64 seq; - }; - - /** -+ * struct nbcon_write_context - Context handed to the nbcon write callbacks -+ * @ctxt: The core console context -+ * @outbuf: Pointer to the text buffer for output -+ * @len: Length to write -+ * @unsafe_takeover: If a hostile takeover in an unsafe state has occurred -+ */ -+struct nbcon_write_context { -+ struct nbcon_context __private ctxt; -+ char *outbuf; -+ unsigned int len; -+ bool unsafe_takeover; -+}; -+ -+/** - * struct console - The console descriptor structure - * @name: The name of the console driver - * @write: Write callback to output messages (Optional) -@@ -277,6 +295,7 @@ struct nbcon_context { - * @data: Driver private data - * @node: hlist node for the console list - * -+ * @write_atomic: Write callback for atomic context - * @nbcon_state: State for nbcon consoles - * @nbcon_seq: Sequence number of the next record for nbcon to print - * @pbufs: Pointer to nbcon private buffer -@@ -301,6 +320,8 @@ struct console { - struct hlist_node node; - - /* nbcon console specific members */ -+ bool (*write_atomic)(struct console *con, -+ struct nbcon_write_context *wctxt); - atomic_t __private nbcon_state; - atomic_long_t __private nbcon_seq; - struct printk_buffers *pbufs; ---- a/kernel/printk/internal.h -+++ b/kernel/printk/internal.h -@@ -130,3 +130,9 @@ struct printk_message { - }; - - bool other_cpu_in_panic(void); -+bool printk_get_next_message(struct printk_message *pmsg, u64 seq, -+ bool is_extended, bool may_supress); -+ -+#ifdef CONFIG_PRINTK -+void console_prepend_dropped(struct printk_message *pmsg, unsigned long dropped); -+#endif ---- a/kernel/printk/nbcon.c -+++ b/kernel/printk/nbcon.c -@@ -221,7 +221,6 @@ void nbcon_seq_force(struct console *con - * nbcon_seq_force() was used or the current context no longer owns the - * console. In the later case, it will stop printing anyway. - */ --__maybe_unused - static void nbcon_seq_try_update(struct nbcon_context *ctxt, u64 new_seq) - { - unsigned long nbcon_seq = __seq_to_nbcon_seq(ctxt->seq); -@@ -755,7 +754,6 @@ static bool nbcon_context_can_proceed(st - * - * Internal helper to avoid duplicated code. - */ --__maybe_unused - static bool __nbcon_context_update_unsafe(struct nbcon_context *ctxt, bool unsafe) - { - struct console *con = ctxt->console; -@@ -785,6 +783,110 @@ static bool __nbcon_context_update_unsaf - } - - /** -+ * nbcon_emit_next_record - Emit a record in the acquired context -+ * @wctxt: The write context that will be handed to the write function -+ * -+ * Return: True if this context still owns the console. False if -+ * ownership was handed over or taken. -+ * -+ * When this function returns false then the calling context no longer owns -+ * the console and is no longer allowed to go forward. In this case it must -+ * back out immediately and carefully. The buffer content is also no longer -+ * trusted since it no longer belongs to the calling context. If the caller -+ * wants to do more it must reacquire the console first. -+ * -+ * When true is returned, @wctxt->ctxt.backlog indicates whether there are -+ * still records pending in the ringbuffer, -+ */ -+__maybe_unused -+static bool nbcon_emit_next_record(struct nbcon_write_context *wctxt) -+{ -+ struct nbcon_context *ctxt = &ACCESS_PRIVATE(wctxt, ctxt); -+ struct console *con = ctxt->console; -+ bool is_extended = console_srcu_read_flags(con) & CON_EXTENDED; -+ struct printk_message pmsg = { -+ .pbufs = ctxt->pbufs, -+ }; -+ unsigned long con_dropped; -+ struct nbcon_state cur; -+ unsigned long dropped; -+ bool done; -+ -+ /* -+ * The printk buffers are filled within an unsafe section. This -+ * prevents NBCON_PRIO_NORMAL and NBCON_PRIO_EMERGENCY from -+ * clobbering each other. -+ */ -+ -+ if (!nbcon_context_enter_unsafe(ctxt)) -+ return false; -+ -+ ctxt->backlog = printk_get_next_message(&pmsg, ctxt->seq, is_extended, true); -+ if (!ctxt->backlog) -+ return nbcon_context_exit_unsafe(ctxt); -+ -+ /* -+ * @con->dropped is not protected in case of an unsafe hostile -+ * takeover. In that situation the update can be racy so -+ * annotate it accordingly. -+ */ -+ con_dropped = data_race(READ_ONCE(con->dropped)); -+ -+ dropped = con_dropped + pmsg.dropped; -+ if (dropped && !is_extended) -+ console_prepend_dropped(&pmsg, dropped); -+ -+ if (!nbcon_context_exit_unsafe(ctxt)) -+ return false; -+ -+ /* For skipped records just update seq/dropped in @con. */ -+ if (pmsg.outbuf_len == 0) -+ goto update_con; -+ -+ /* Initialize the write context for driver callbacks. */ -+ wctxt->outbuf = &pmsg.pbufs->outbuf[0]; -+ wctxt->len = pmsg.outbuf_len; -+ nbcon_state_read(con, &cur); -+ wctxt->unsafe_takeover = cur.unsafe_takeover; -+ -+ if (con->write_atomic) { -+ done = con->write_atomic(con, wctxt); -+ } else { -+ nbcon_context_release(ctxt); -+ WARN_ON_ONCE(1); -+ done = false; -+ } -+ -+ /* If not done, the emit was aborted. */ -+ if (!done) -+ return false; -+ -+ /* -+ * Since any dropped message was successfully output, reset the -+ * dropped count for the console. -+ */ -+ dropped = 0; -+update_con: -+ /* -+ * The dropped count and the sequence number are updated within an -+ * unsafe section. This limits update races to the panic context and -+ * allows the panic context to win. -+ */ -+ -+ if (!nbcon_context_enter_unsafe(ctxt)) -+ return false; -+ -+ if (dropped != con_dropped) { -+ /* Counterpart to the READ_ONCE() above. */ -+ WRITE_ONCE(con->dropped, dropped); -+ } -+ -+ nbcon_seq_try_update(ctxt, pmsg.seq + 1); -+ -+ return nbcon_context_exit_unsafe(ctxt); -+} -+ -+/** - * nbcon_alloc - Allocate buffers needed by the nbcon console - * @con: Console to allocate buffers for - * ---- a/kernel/printk/printk.c -+++ b/kernel/printk/printk.c -@@ -698,9 +698,6 @@ static ssize_t msg_print_ext_body(char * - return len; - } - --static bool printk_get_next_message(struct printk_message *pmsg, u64 seq, -- bool is_extended, bool may_supress); -- - /* /dev/kmsg - userspace message inject/listen interface */ - struct devkmsg_user { - atomic64_t seq; -@@ -2733,7 +2730,7 @@ static void __console_unlock(void) - * If @pmsg->pbufs->outbuf is modified, @pmsg->outbuf_len is updated. - */ - #ifdef CONFIG_PRINTK --static void console_prepend_dropped(struct printk_message *pmsg, unsigned long dropped) -+void console_prepend_dropped(struct printk_message *pmsg, unsigned long dropped) - { - struct printk_buffers *pbufs = pmsg->pbufs; - const size_t scratchbuf_sz = sizeof(pbufs->scratchbuf); -@@ -2787,8 +2784,8 @@ static void console_prepend_dropped(stru - * of @pmsg are valid. (See the documentation of struct printk_message - * for information about the @pmsg fields.) - */ --static bool printk_get_next_message(struct printk_message *pmsg, u64 seq, -- bool is_extended, bool may_suppress) -+bool printk_get_next_message(struct printk_message *pmsg, u64 seq, -+ bool is_extended, bool may_suppress) - { - static int panic_console_dropped; - -- cgit v1.2.3