From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kOPtN-0003j8-5A for kexec@lists.infradead.org; Fri, 02 Oct 2020 18:34:55 +0000 Received: by mail-ot1-f70.google.com with SMTP id z20so1004528otk.5 for ; Fri, 02 Oct 2020 11:34:48 -0700 (PDT) MIME-Version: 1.0 References: <20201002134248.21006-1-matthias.bgg@kernel.org> In-Reply-To: <20201002134248.21006-1-matthias.bgg@kernel.org> From: Bhupesh Sharma Date: Sat, 3 Oct 2020 00:04:35 +0530 Message-ID: Subject: Re: [PATCH v4] arm64: Add purgatory printing List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: matthias.bgg@kernel.org Cc: geoff@infradead.org, Bhupesh SHARMA , Simon Horman , kexec mailing list , Matthias Brugger Hello Matthias, Thanks for the updated revision. On Fri, Oct 2, 2020 at 7:13 PM wrote: > > From: Matthias Brugger > > Add option to allow purgatory printing on arm64 hardware > by passing the console name which should be used. > Based on a patch by Geoff Levand. > > Cc: Geoff Levand > Signed-off-by: Matthias Brugger > > --- > > Changes in v4: > - fix snprintf error handling > > Changes in v3: > - check return value of snprintf > > Changes in v2: > - use sizeof(buffer) > - user serial command option instead of console > - reduce buffer to size 10 > - use snprintf > - fix error handling for wrong serial console parameter > - Update help information > > kexec/arch/arm64/include/arch/options.h | 6 ++- > kexec/arch/arm64/kexec-arm64.c | 71 +++++++++++++++++++++++++ > purgatory/arch/arm64/purgatory-arm64.c | 17 +++++- > 3 files changed, 92 insertions(+), 2 deletions(-) > > diff --git a/kexec/arch/arm64/include/arch/options.h b/kexec/arch/arm64/include/arch/options.h > index a17d933..8c695f3 100644 > --- a/kexec/arch/arm64/include/arch/options.h > +++ b/kexec/arch/arm64/include/arch/options.h > @@ -5,7 +5,8 @@ > #define OPT_DTB ((OPT_MAX)+1) > #define OPT_INITRD ((OPT_MAX)+2) > #define OPT_REUSE_CMDLINE ((OPT_MAX)+3) > -#define OPT_ARCH_MAX ((OPT_MAX)+4) > +#define OPT_SERIAL ((OPT_MAX)+4) > +#define OPT_ARCH_MAX ((OPT_MAX)+5) > > #define KEXEC_ARCH_OPTIONS \ > KEXEC_OPTIONS \ > @@ -13,6 +14,7 @@ > { "command-line", 1, NULL, OPT_APPEND }, \ > { "dtb", 1, NULL, OPT_DTB }, \ > { "initrd", 1, NULL, OPT_INITRD }, \ > + { "serial", 1, NULL, OPT_SERIAL }, \ > { "ramdisk", 1, NULL, OPT_INITRD }, \ > { "reuse-cmdline", 0, NULL, OPT_REUSE_CMDLINE }, \ > > @@ -25,6 +27,7 @@ static const char arm64_opts_usage[] __attribute__ ((unused)) = > " --command-line=STRING Set the kernel command line to STRING.\n" > " --dtb=FILE Use FILE as the device tree blob.\n" > " --initrd=FILE Use FILE as the kernel initial ramdisk.\n" > +" --serial=STRING Name of console used for purgatory printing. (e.g. ttyAMA0)\n" > " --ramdisk=FILE Use FILE as the kernel initial ramdisk.\n" > " --reuse-cmdline Use kernel command line from running system.\n"; > > @@ -32,6 +35,7 @@ struct arm64_opts { > const char *command_line; > const char *dtb; > const char *initrd; > + const char *console; > }; > > extern struct arm64_opts arm64_opts; > diff --git a/kexec/arch/arm64/kexec-arm64.c b/kexec/arch/arm64/kexec-arm64.c > index 45ebc54..6f572ed 100644 > --- a/kexec/arch/arm64/kexec-arm64.c > +++ b/kexec/arch/arm64/kexec-arm64.c > @@ -165,6 +165,8 @@ int arch_process_options(int argc, char **argv) > break; > case OPT_KEXEC_FILE_SYSCALL: > do_kexec_file_syscall = 1; > + case OPT_SERIAL: > + arm64_opts.console = optarg; > break; > default: > break; /* Ignore core and unknown options. */ > @@ -180,12 +182,72 @@ int arch_process_options(int argc, char **argv) > dbgprintf("%s:%d: dtb: %s\n", __func__, __LINE__, > (do_kexec_file_syscall && arm64_opts.dtb ? "(ignored)" : > arm64_opts.dtb)); > + dbgprintf("%s:%d: console: %s\n", __func__, __LINE__, > + arm64_opts.console); > + > if (do_kexec_file_syscall) > arm64_opts.dtb = NULL; > > return 0; > } > > +/** > + * find_purgatory_sink - Find a sink for purgatory output. > + */ > + > +static uint64_t find_purgatory_sink(const char *console) > +{ > + int fd, ret; > + char device[255], mem[255]; > + struct stat sb; > + char buffer[10]; > + uint64_t iomem = 0x0; > + > + if (!console) > + return 0; > + > + ret = snprintf(device, sizeof(device), "/sys/class/tty/%s", console); > + if (ret < 0 || ret >= sizeof(device)) { > + fprintf(stderr, "snprintf failed: %s\n", strerror(errno)); > + return 0; > + } > + > + if (stat(device, &sb) || !S_ISDIR(sb.st_mode)) { > + fprintf(stderr, "kexec: %s: No valid console found for %s\n", > + __func__, device); > + return 0; > + } > + > + ret = snprintf(mem, sizeof(mem), "%s%s", device, "/iomem_base"); > + if (ret < 0 || ret >= sizeof(mem)) { > + fprintf(stderr, "snprintf failed: %s\n", strerror(errno)); > + return 0; > + } > + > + printf("console memory read from %s\n", mem); > + > + fd = open(mem, O_RDONLY); > + if (fd < 0) { > + fprintf(stderr, "kexec: %s: No able to open %s\n", > + __func__, mem); > + return 0; > + } > + > + memset(buffer, '\0', sizeof(buffer)); > + ret = read(fd, buffer, sizeof(buffer)); > + if (ret < 0) { > + fprintf(stderr, "kexec: %s: not able to read fd\n", __func__); > + close(fd); > + return 0; > + } > + > + sscanf(buffer, "%lx", &iomem); > + printf("console memory is at %#lx\n", iomem); > + > + close(fd); > + return iomem; > +} > + > /** > * struct dtb - Info about a binary device tree. > * > @@ -637,6 +699,7 @@ int arm64_load_other_segments(struct kexec_info *info, > unsigned long hole_min; > unsigned long hole_max; > unsigned long initrd_end; > + uint64_t purgatory_sink; > char *initrd_buf = NULL; > struct dtb dtb; > char command_line[COMMAND_LINE_SIZE] = ""; > @@ -654,6 +717,11 @@ int arm64_load_other_segments(struct kexec_info *info, > command_line[sizeof(command_line) - 1] = 0; > } > > + purgatory_sink = find_purgatory_sink(arm64_opts.console); > + > + dbgprintf("%s:%d: purgatory sink: 0x%" PRIx64 "\n", __func__, __LINE__, > + purgatory_sink); > + > if (arm64_opts.dtb) { > dtb.name = "dtb_user"; > dtb.buf = slurp_file(arm64_opts.dtb, &dtb.size); > @@ -742,6 +810,9 @@ int arm64_load_other_segments(struct kexec_info *info, > > info->entry = (void *)elf_rel_get_addr(&info->rhdr, "purgatory_start"); > > + elf_rel_set_symbol(&info->rhdr, "arm64_sink", &purgatory_sink, > + sizeof(purgatory_sink)); > + > elf_rel_set_symbol(&info->rhdr, "arm64_kernel_entry", &image_base, > sizeof(image_base)); > > diff --git a/purgatory/arch/arm64/purgatory-arm64.c b/purgatory/arch/arm64/purgatory-arm64.c > index fe50fcf..b4d8578 100644 > --- a/purgatory/arch/arm64/purgatory-arm64.c > +++ b/purgatory/arch/arm64/purgatory-arm64.c > @@ -5,15 +5,30 @@ > #include > #include > > +/* Symbols set by kexec. */ > + > +uint8_t *arm64_sink __attribute__ ((section ("data"))); > +extern void (*arm64_kernel_entry)(uint64_t, uint64_t, uint64_t, uint64_t); > +extern uint64_t arm64_dtb_addr; > + > void putchar(int ch) > { > - /* Nothing for now */ > + if (!arm64_sink) > + return; > + > + *arm64_sink = ch; > + > + if (ch == '\n') > + *arm64_sink = '\r'; > } > > void post_verification_setup_arch(void) > { > + printf("purgatory: booting kernel now\n"); > } > > void setup_arch(void) > { > + printf("purgatory: entry=%lx\n", (unsigned long)arm64_kernel_entry); > + printf("purgatory: dtb=%lx\n", arm64_dtb_addr); > } > -- > 2.28.0 Looks good to me, so: Acked-by: Bhupesh Sharma Thanks. _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec