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It appends > to whichever line was most recently opened by a printk(). If a > pr_err() or pr_warn() from another CPU or an interrupt handler > preempts the pr_info() / pr_cont() sequence, it closes the > continuation between the fragments. This can cause parts of the > pstore registration message to appear at the wrong log level and be > interleaved with other messages. > > Furthermore, this causes the detection of new warning and error > messages in the kernel log to be unreliable. > > Format the registration line into a seq_buf and emit it with a > single pr_info() call, making the line atomic with respect to > concurrent printk() callers. No functional change to registration. > > Signed-off-by: Kartik Rajput > --- > Changes in v2: > - Use a seq_buf to build the registration line instead of scnprintf() > calls. > - Link to v1: https://lore.kernel.org/all/20260424095820.1433700-1-kkartik@nvidia.com/ > --- > fs/pstore/zone.c | 23 +++++++++++++---------- > 1 file changed, 13 insertions(+), 10 deletions(-) > > diff --git a/fs/pstore/zone.c b/fs/pstore/zone.c > index a3b003f9a3a0..004a5d5f376b 100644 > --- a/fs/pstore/zone.c > +++ b/fs/pstore/zone.c > @@ -12,6 +12,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -1301,6 +1302,10 @@ int register_pstore_zone(struct pstore_zone_info *info) > { > int err = -EINVAL; > struct psz_context *cxt = &pstore_zone_cxt; > + char buf[256]; > + struct seq_buf s; > + > + seq_buf_init(&s, buf, sizeof(buf)); > > if (info->total_size < 4096) { > pr_warn("total_size must be >= 4096\n"); > @@ -1383,30 +1388,28 @@ int register_pstore_zone(struct pstore_zone_info *info) > } > cxt->pstore.data = cxt; > > - pr_info("registered %s as backend for", info->name); > cxt->pstore.max_reason = info->max_reason; > cxt->pstore.name = info->name; > if (info->kmsg_size) { > cxt->pstore.flags |= PSTORE_FLAGS_DMESG; > - pr_cont(" kmsg(%s", > - kmsg_dump_reason_str(cxt->pstore.max_reason)); > - if (cxt->pstore_zone_info->panic_write) > - pr_cont(",panic_write"); > - pr_cont(")"); > + seq_buf_printf(&s, " kmsg(%s%s)", > + kmsg_dump_reason_str(cxt->pstore.max_reason), > + cxt->pstore_zone_info->panic_write ? ",panic_write" : ""); > } > if (info->pmsg_size) { > cxt->pstore.flags |= PSTORE_FLAGS_PMSG; > - pr_cont(" pmsg"); > + seq_buf_puts(&s, " pmsg"); > } > if (info->console_size) { > cxt->pstore.flags |= PSTORE_FLAGS_CONSOLE; > - pr_cont(" console"); > + seq_buf_puts(&s, " console"); > } > if (info->ftrace_size) { > cxt->pstore.flags |= PSTORE_FLAGS_FTRACE; > - pr_cont(" ftrace"); > + seq_buf_puts(&s, " ftrace"); > } > - pr_cont("\n"); > + > + pr_info("registered %s as backend for%s\n", info->name, seq_buf_str(&s)); > > err = pstore_register(&cxt->pstore); > if (err) { Acked-by: Jon Hunter Jon -- nvpublic