From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 35B581A01CC for ; Tue, 30 Jun 2015 22:25:11 +1000 (AEST) Received: from e23smtp02.au.ibm.com (e23smtp02.au.ibm.com [202.81.31.144]) (using TLSv1 with cipher CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 0E5461402D2 for ; Tue, 30 Jun 2015 22:25:11 +1000 (AEST) Received: from /spool/local by e23smtp02.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 30 Jun 2015 22:25:08 +1000 Received: from d23relay10.au.ibm.com (d23relay10.au.ibm.com [9.190.26.77]) by d23dlp03.au.ibm.com (Postfix) with ESMTP id D8B53357804C for ; Tue, 30 Jun 2015 22:25:06 +1000 (EST) Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay10.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t5UCOwEn63897694 for ; Tue, 30 Jun 2015 22:25:06 +1000 Received: from d23av02.au.ibm.com (localhost [127.0.0.1]) by d23av02.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t5UCOXFo002948 for ; Tue, 30 Jun 2015 22:24:33 +1000 From: Nikunj A Dadhania To: Thomas Huth Cc: linuxppc-dev@ozlabs.org, segher@kernel.crashing.org, aik@ozlabs.ru, dvaleev@suse.com Subject: Re: [PATCH SLOF v3 5/5] disk-label: add support for booting from GPT FAT partition In-Reply-To: <20150630132834.16643eb5@thh440s> References: <1435662081-4293-1-git-send-email-nikunj@linux.vnet.ibm.com> <1435662081-4293-6-git-send-email-nikunj@linux.vnet.ibm.com> <20150630132834.16643eb5@thh440s> Date: Tue, 30 Jun 2015 17:54:14 +0530 Message-ID: <87h9ppz8nl.fsf@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Thomas Huth writes: > Sorry, every time I look at this gpt stuff, my eyes stumble > over something new ... No worries :-) > On Tue, 30 Jun 2015 16:31:21 +0530 > Nikunj A Dadhania wrote: > >> For a GPT+LVM combination disk, older bootloader that does not support >> LVM, cannot load kernel from LVM. >> >> The patch adds support to read from BASIC_DATA UUID partitions for the >> case that the OS installer has installed the CHRP-BOOT config on a FAT >> file system. >> >> Makes GPT detection robust >> * Check for Protective MBR Magic >> * Check for valid GPT Signature >> * Boundary check for allocated block size before reading into the >> buffer >> >> Signed-off-by: Nikunj A Dadhania >> --- >> slof/fs/packages/disk-label.fs | 99 +++++++++++++++++++++++++++++++++--------- >> 1 file changed, 79 insertions(+), 20 deletions(-) >> >> diff --git a/slof/fs/packages/disk-label.fs b/slof/fs/packages/disk-label.fs >> index 347dc5d..5267ddb 100644 >> --- a/slof/fs/packages/disk-label.fs >> +++ b/slof/fs/packages/disk-label.fs > ... >> +\ The routine checks whether the protective MBR has GPT ID and then >> +\ reads the gpt data from the sector. Also set the seek position and >> +\ the partition size used in caller routines. >> + >> +: get-gpt-partition ( -- true|false ) >> + no-gpt? IF false EXIT THEN >> + debug-disk-label? IF cr ." GPT partition found " cr THEN >> + 1 read-disk-buf >> + disk-buf gpt>part-entry-lba x@-le >> block-size * to seek-pos >> disk-buf gpt>part-entry-size l@-le to gpt-part-size >> - disk-buf gpt>num-part-entry l@-le dup 0= IF false EXIT THEN >> + gpt-part-size disk-buf-size > IF >> + cr ." GPT part size exceeds buffer allocated " cr >> + false exit >> + THEN >> + disk-buf gpt>signature x@ GPT-SIGNATURE = >> +; >> + >> +: load-from-gpt-prep-partition ( addr -- size ) >> + get-gpt-partition 0= IF false EXIT THEN >> + disk-buf gpt>num-part-entry l@-le dup 0= IF false exit THEN >> 1+ 1 ?DO >> seek-pos 0 seek drop >> disk-buf gpt-part-size read drop gpt-prep-partition? IF >> - debug-disk-label? IF >> - ." GPT PReP partition found " cr >> - THEN >> - disk-buf gpt-part-entry>first-lba x@-le >> - disk-buf gpt-part-entry>last-lba x@-le >> - over - 1+ ( addr offset len ) >> - swap ( addr len offset ) >> - block-size * to part-offset >> - 0 0 seek drop ( addr len ) >> - block-size * read ( size ) >> + debug-disk-label? IF ." GPT PReP partition found " cr THEN >> + disk-buf gpt-part-entry>first-lba x@-le ( addr first-lba ) >> + disk-buf gpt-part-entry>last-lba x@-le ( addr first-lba last-lba) >> + over - 1+ ( addr first-lba blocks ) >> + swap ( addr blocks first-lba ) >> + block-size * to part-offset ( addr blocks ) >> + 0 0 seek drop ( addr blocks ) >> + block-size * read ( size ) >> + UNLOOP EXIT >> + THEN >> + seek-pos gpt-part-size i * + to seek-pos > > Is this the right way to update the seek pos? Good catch !! its jumping ahead, should go in the order of 128byte (gpt-part-size) > Looks somewhat suspicious > to me, shouldn't this rather be: > > seek-pos gpt-part-size + to seek-pos Would use this. Updated patch attached. > or maybe if you store the base value somewhere instead, something like: > > seek-pos-base gpt-part-size i * + to seek-pos > > ? > >> + LOOP >> + false >> +; >> + >> +: try-gpt-dos-partition ( -- true|false ) >> + get-gpt-partition 0= IF false EXIT THEN >> + disk-buf gpt>num-part-entry l@-le dup 0= IF false EXIT THEN >> + 1+ 1 ?DO >> + seek-pos 0 seek drop >> + disk-buf gpt-part-size read drop >> + gpt-basic-data-partition? IF >> + debug-disk-label? IF ." GPT BASIC DATA partition found " cr THEN >> + disk-buf gpt-part-entry>first-lba x@-le ( first-lba ) >> + dup to part-start ( first-lba ) >> + disk-buf gpt-part-entry>last-lba x@-le ( first-lba last-lba ) >> + over - 1+ ( first-lba s1 ) >> + block-size * to part-size ( first-lba ) >> + block-size * to part-offset ( ) >> + 0 0 seek drop >> + disk-buf block-size read drop >> + disk-buf fat-bootblock? ( true|false ) >> UNLOOP EXIT >> THEN >> seek-pos gpt-part-size i * + to seek-pos > > dito (so this bug was likely there before?) Seems was working because it happens to be the first partition. If not would have failed. disk-label: add support for booting from GPT FAT partition For a GPT+LVM combination disk, older bootloader that does not support LVM, cannot load kernel from LVM. The patch adds support to read from BASIC_DATA UUID partitions for the case that the OS installer has installed the CHRP-BOOT config on a FAT file system. Makes GPT detection robust * Fix bug in seek-pos updation code * Check for Protective MBR Magic * Check for valid GPT Signature * Boundary check for allocated block size before reading into the buffer Signed-off-by: Nikunj A Dadhania diff --git a/slof/fs/packages/disk-label.fs b/slof/fs/packages/disk-label.fs index 347dc5d..fa5df27 100644 --- a/slof/fs/packages/disk-label.fs +++ b/slof/fs/packages/disk-label.fs @@ -179,7 +179,8 @@ CONSTANT /gpt-part-entry \ This word returns true if the currently loaded disk-buf has _NO_ GPT partition id : no-gpt? ( -- true|false ) 0 read-disk-buf - 1 partition>part-entry part-entry>id c@ ee <> + 1 partition>part-entry part-entry>id c@ ee <> IF true EXIT THEN + disk-buf mbr>magic w@-le aa55 <> ; : pc-extended-partition? ( part-entry-addr -- true|false ) @@ -267,7 +268,10 @@ CONSTANT /gpt-part-entry : try-dos-partition ( -- okay? ) \ Read partition table and check magic. - no-mbr? IF cr ." No DOS disk-label found." cr false EXIT THEN + no-mbr? IF + debug-disk-label? IF cr ." No DOS disk-label found." cr THEN + false EXIT + THEN count-dos-logical-partitions TO dos-logical-partitions @@ -377,31 +381,85 @@ AA268B49521E5A8B CONSTANT GPT-PREP-PARTITION-4 8 + x@ GPT-PREP-PARTITION-4 = ; -: load-from-gpt-prep-partition ( addr -- size ) - no-gpt? IF drop false EXIT THEN - debug-disk-label? IF - cr ." GPT partition found " cr - THEN - 1 read-disk-buf disk-buf gpt>part-entry-lba l@-le +\ Check for GPT MSFT BASIC DATA GUID - fat based +EBD0A0A2 CONSTANT GPT-BASIC-DATA-PARTITION-1 +B9E5 CONSTANT GPT-BASIC-DATA-PARTITION-2 +4433 CONSTANT GPT-BASIC-DATA-PARTITION-3 +87C068B6B72699C7 CONSTANT GPT-BASIC-DATA-PARTITION-4 + +: gpt-basic-data-partition? ( -- true|false ) + disk-buf gpt-part-entry>part-type-guid + dup l@-le GPT-BASIC-DATA-PARTITION-1 <> IF drop false EXIT THEN + dup 4 + w@-le GPT-BASIC-DATA-PARTITION-2 <> IF drop false EXIT THEN + dup 6 + w@-le GPT-BASIC-DATA-PARTITION-3 <> IF drop false EXIT THEN + 8 + x@ GPT-BASIC-DATA-PARTITION-4 = +; + +\ +\ GPT Signature +\ ("EFI PART", 45h 46h 49h 20h 50h 41h 52h 54h) +\ +4546492050415254 CONSTANT GPT-SIGNATURE + +\ The routine checks whether the protective MBR has GPT ID and then +\ reads the gpt data from the sector. Also set the seek position and +\ the partition size used in caller routines. + +: get-gpt-partition ( -- true|false ) + no-gpt? IF false EXIT THEN + debug-disk-label? IF cr ." GPT partition found " cr THEN + 1 read-disk-buf + disk-buf gpt>part-entry-lba x@-le block-size * to seek-pos disk-buf gpt>part-entry-size l@-le to gpt-part-size - disk-buf gpt>num-part-entry l@-le dup 0= IF false EXIT THEN + gpt-part-size disk-buf-size > IF + cr ." GPT part size exceeds buffer allocated " cr + false exit + THEN + disk-buf gpt>signature x@ GPT-SIGNATURE = +; + +: load-from-gpt-prep-partition ( addr -- size ) + get-gpt-partition 0= IF false EXIT THEN + disk-buf gpt>num-part-entry l@-le dup 0= IF false exit THEN 1+ 1 ?DO seek-pos 0 seek drop disk-buf gpt-part-size read drop gpt-prep-partition? IF - debug-disk-label? IF - ." GPT PReP partition found " cr - THEN - disk-buf gpt-part-entry>first-lba x@-le - disk-buf gpt-part-entry>last-lba x@-le - over - 1+ ( addr offset len ) - swap ( addr len offset ) - block-size * to part-offset - 0 0 seek drop ( addr len ) - block-size * read ( size ) + debug-disk-label? IF ." GPT PReP partition found " cr THEN + disk-buf gpt-part-entry>first-lba x@-le ( addr first-lba ) + disk-buf gpt-part-entry>last-lba x@-le ( addr first-lba last-lba) + over - 1+ ( addr first-lba blocks ) + swap ( addr blocks first-lba ) + block-size * to part-offset ( addr blocks ) + 0 0 seek drop ( addr blocks ) + block-size * read ( size ) + UNLOOP EXIT + THEN + seek-pos gpt-part-size + to seek-pos + LOOP + false +; + +: try-gpt-dos-partition ( -- true|false ) + get-gpt-partition 0= IF false EXIT THEN + disk-buf gpt>num-part-entry l@-le dup 0= IF false EXIT THEN + 1+ 1 ?DO + seek-pos 0 seek drop + disk-buf gpt-part-size read drop + gpt-basic-data-partition? IF + debug-disk-label? IF ." GPT BASIC DATA partition found " cr THEN + disk-buf gpt-part-entry>first-lba x@-le ( first-lba ) + dup to part-start ( first-lba ) + disk-buf gpt-part-entry>last-lba x@-le ( first-lba last-lba ) + over - 1+ ( first-lba s1 ) + block-size * to part-size ( first-lba ) + block-size * to part-offset ( ) + 0 0 seek drop + disk-buf block-size read drop + disk-buf fat-bootblock? ( true|false ) UNLOOP EXIT THEN - seek-pos gpt-part-size i * + to seek-pos + seek-pos gpt-part-size + to seek-pos LOOP false ; @@ -491,7 +549,7 @@ AA268B49521E5A8B CONSTANT GPT-PREP-PARTITION-4 debug-disk-label? IF ." Trying CHRP boot " .s cr THEN 1 disk-chrp-boot ! - dup load-chrp-boot-file ?dup 0 <> IF .s cr nip EXIT THEN + dup load-chrp-boot-file ?dup 0 <> IF nip EXIT THEN 0 disk-chrp-boot ! debug-disk-label? IF ." Trying GPT boot " .s cr THEN @@ -591,6 +649,7 @@ AA268B49521E5A8B CONSTANT GPT-PREP-PARTITION-4 : try-partitions ( -- found? ) try-dos-partition IF try-files EXIT THEN + try-gpt-dos-partition IF try-files EXIT THEN \ try-iso9660-partition IF try-files EXIT THEN \ ... more partition types here... false