virtio_blk: set the zone write granularitygrafted

virtblk_read_zoned_limits() reads the write granularity that the device
reports in virtio_blk_zoned_characteristics and assigns it to the
physical block size and to io_min, but never to the limit that is named
after it. queue_limits.zone_write_granularity is left at zero, so
blk_validate_zoned_limits() raises it to the logical block size:

	if (lim->zone_write_granularity < lim->logical_block_size)
		lim->zone_write_granularity = lim->logical_block_size;

A device that reports a granularity coarser than its logical block size,
which is what the field exists to express, therefore has it silently
reduced. A 512e host managed disk passed through to a guest reports a
logical block size of 512 and a write granularity of 4096, and the guest
ends up with a zone write granularity of 512.

bio_split_alignment() returns lim->zone_write_granularity if it is non-zero
and bio_split_io_at() may split a bio with as per bio_split_alignment().
This can real to the write getting rejected by the host drive, as the write
is not aligned to the physical block size.

zonefs also takes its block size from bdev_zone_write_granularity(), so it
would incorrectly use 512 on a disk that requires 4096.

sd_zbc_read_zones() sets the limit from the physical block size for the
same reason. NVMe ZNS and null_blk leave it unset, but the fallback
gives the right answer for them, as their write granularity is the
logical block size. virtio carries a separate value that may exceed it.

Set the zone write granularity from the value that the device reports.

Fixes: 95bfec41bd3d ("virtio-blk: add support for zoned block devices")
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Link: https://patch.msgid.link/20260918140641.2031075-2-cassel@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 366 insertions, 0 deletions

diff --git a/scripts/markup_oops.pl b/scripts/markup_oops.pl
new file mode 100755
index 000000000..e476caf52
--- /dev/null
+++ b/scripts/markup_oops.pl
@@ -0,0 +1,366 @@
+#!/usr/bin/env perl
+# SPDX-License-Identifier: GPL-2.0-only
+
+use File::Basename;
+use Math::BigInt;
+use Getopt::Long;
+
+# Copyright 2008, Intel Corporation
+#
+# This file is part of the Linux kernel
+#
+# Authors:
+# 	Arjan van de Ven <arjan@linux.intel.com>
+
+
+my $cross_compile = "";
+my $vmlinux_name = "";
+my $modulefile = "";
+
+# Get options
+Getopt::Long::GetOptions(
+	'cross-compile|c=s'	=> \$cross_compile,
+	'module|m=s'		=> \$modulefile,
+	'help|h'		=> \&usage,
+) || usage ();
+my $vmlinux_name = $ARGV[0];
+if (!defined($vmlinux_name)) {
+	my $kerver = `uname -r`;
+	chomp($kerver);
+	$vmlinux_name = "/lib/modules/$kerver/build/vmlinux";
+	print "No vmlinux specified, assuming $vmlinux_name\n";
+}
+my $filename = $vmlinux_name;
+
+# Parse the oops to find the EIP value
+
+my $target = "0";
+my $function;
+my $module = "";
+my $func_offset = 0;
+my $vmaoffset = 0;
+
+my %regs;
+
+
+sub parse_x86_regs
+{
+	my ($line) = @_;
+	if ($line =~ /EAX: ([0-9a-f]+) EBX: ([0-9a-f]+) ECX: ([0-9a-f]+) EDX: ([0-9a-f]+)/) {
+		$regs{"%eax"} = $1;
+		$regs{"%ebx"} = $2;
+		$regs{"%ecx"} = $3;
+		$regs{"%edx"} = $4;
+	}
+	if ($line =~ /ESI: ([0-9a-f]+) EDI: ([0-9a-f]+) EBP: ([0-9a-f]+) ESP: ([0-9a-f]+)/) {
+		$regs{"%esi"} = $1;
+		$regs{"%edi"} = $2;
+		$regs{"%esp"} = $4;
+	}
+	if ($line =~ /RAX: ([0-9a-f]+) RBX: ([0-9a-f]+) RCX: ([0-9a-f]+)/) {
+		$regs{"%eax"} = $1;
+		$regs{"%ebx"} = $2;
+		$regs{"%ecx"} = $3;
+	}
+	if ($line =~ /RDX: ([0-9a-f]+) RSI: ([0-9a-f]+) RDI: ([0-9a-f]+)/) {
+		$regs{"%edx"} = $1;
+		$regs{"%esi"} = $2;
+		$regs{"%edi"} = $3;
+	}
+	if ($line =~ /RBP: ([0-9a-f]+) R08: ([0-9a-f]+) R09: ([0-9a-f]+)/) {
+		$regs{"%r08"} = $2;
+		$regs{"%r09"} = $3;
+	}
+	if ($line =~ /R10: ([0-9a-f]+) R11: ([0-9a-f]+) R12: ([0-9a-f]+)/) {
+		$regs{"%r10"} = $1;
+		$regs{"%r11"} = $2;
+		$regs{"%r12"} = $3;
+	}
+	if ($line =~ /R13: ([0-9a-f]+) R14: ([0-9a-f]+) R15: ([0-9a-f]+)/) {
+		$regs{"%r13"} = $1;
+		$regs{"%r14"} = $2;
+		$regs{"%r15"} = $3;
+	}
+}
+
+sub reg_name
+{
+	my ($reg) = @_;
+	$reg =~ s/r(.)x/e\1x/;
+	$reg =~ s/r(.)i/e\1i/;
+	$reg =~ s/r(.)p/e\1p/;
+	return $reg;
+}
+
+sub process_x86_regs
+{
+	my ($line, $cntr) = @_;
+	my $str = "";
+	if (length($line) < 40) {
+		return ""; # not an asm istruction
+	}
+
+	# find the arguments to the instruction
+	if ($line =~ /([0-9a-zA-Z\,\%\(\)\-\+]+)$/) {
+		$lastword = $1;
+	} else {
+		return "";
+	}
+
+	# we need to find the registers that get clobbered,
+	# since their value is no longer relevant for previous
+	# instructions in the stream.
+
+	$clobber = $lastword;
+	# first, remove all memory operands, they're read only
+	$clobber =~ s/\([a-z0-9\%\,]+\)//g;
+	# then, remove everything before the comma, thats the read part
+	$clobber =~ s/.*\,//g;
+
+	# if this is the instruction that faulted, we haven't actually done
+	# the write yet... nothing is clobbered.
+	if ($cntr == 0) {
+		$clobber = "";
+	}
+
+	foreach $reg (keys(%regs)) {
+		my $clobberprime = reg_name($clobber);
+		my $lastwordprime = reg_name($lastword);
+		my $val = $regs{$reg};
+		if ($val =~ /^[0]+$/) {
+			$val = "0";
+		} else {
+			$val =~ s/^0*//;
+		}
+
+		# first check if we're clobbering this register; if we do
+		# we print it with a =>, and then delete its value
+		if ($clobber =~ /$reg/ || $clobberprime =~ /$reg/) {
+			if (length($val) > 0) {
+				$str = $str . " $reg => $val ";
+			}
+			$regs{$reg} = "";
+			$val = "";
+		}
+		# now check if we're reading this register
+		if ($lastword =~ /$reg/ || $lastwordprime =~ /$reg/) {
+			if (length($val) > 0) {
+				$str = $str . " $reg = $val ";
+			}
+		}
+	}
+	return $str;
+}
+
+# parse the oops
+while (<STDIN>) {
+	my $line = $_;
+	if ($line =~ /EIP: 0060:\[\<([a-z0-9]+)\>\]/) {
+		$target = $1;
+	}
+	if ($line =~ /RIP: 0010:\[\<([a-z0-9]+)\>\]/) {
+		$target = $1;
+	}
+	if ($line =~ /EIP is at ([a-zA-Z0-9\_]+)\+0x([0-9a-f]+)\/0x[a-f0-9]/) {
+		$function = $1;
+		$func_offset = $2;
+	}
+	if ($line =~ /RIP: 0010:\[\<[0-9a-f]+\>\]  \[\<[0-9a-f]+\>\] ([a-zA-Z0-9\_]+)\+0x([0-9a-f]+)\/0x[a-f0-9]/) {
+		$function = $1;
+		$func_offset = $2;
+	}
+
+	# check if it's a module
+	if ($line =~ /EIP is at ([a-zA-Z0-9\_]+)\+(0x[0-9a-f]+)\/0x[a-f0-9]+\W\[([a-zA-Z0-9\_\-]+)\]/) {
+		$module = $3;
+	}
+	if ($line =~ /RIP: 0010:\[\<[0-9a-f]+\>\]  \[\<[0-9a-f]+\>\] ([a-zA-Z0-9\_]+)\+(0x[0-9a-f]+)\/0x[a-f0-9]+\W\[([a-zA-Z0-9\_\-]+)\]/) {
+		$module = $3;
+	}
+	parse_x86_regs($line);
+}
+
+my $decodestart = Math::BigInt->from_hex("0x$target") - Math::BigInt->from_hex("0x$func_offset");
+my $decodestop = Math::BigInt->from_hex("0x$target") + 8192;
+if ($target eq "0") {
+	print "No oops found!\n";
+	usage();
+}
+
+# if it's a module, we need to find the .ko file and calculate a load offset
+if ($module ne "") {
+	if ($modulefile eq "") {
+		$modulefile = `modinfo -F filename $module`;
+		chomp($modulefile);
+	}
+	$filename = $modulefile;
+	if ($filename eq "") {
+		print "Module .ko file for $module not found. Aborting\n";
+		exit;
+	}
+	# ok so we found the module, now we need to calculate the vma offset
+	open(FILE, $cross_compile."objdump -dS $filename |") || die "Cannot start objdump";
+	while (<FILE>) {
+		if ($_ =~ /^([0-9a-f]+) \<$function\>\:/) {
+			my $fu = $1;
+			$vmaoffset = Math::BigInt->from_hex("0x$target") - Math::BigInt->from_hex("0x$fu") - Math::BigInt->from_hex("0x$func_offset");
+		}
+	}
+	close(FILE);
+}
+
+my $counter = 0;
+my $state   = 0;
+my $center  = -1;
+my @lines;
+my @reglines;
+
+sub InRange {
+	my ($address, $target) = @_;
+	my $ad = "0x".$address;
+	my $ta = "0x".$target;
+	my $delta = Math::BigInt->from_hex($ad) - Math::BigInt->from_hex($ta);
+
+	if (($delta > -4096) && ($delta < 4096)) {
+		return 1;
+	}
+	return 0;
+}
+
+
+
+# first, parse the input into the lines array, but to keep size down,
+# we only do this for 4Kb around the sweet spot
+
+open(FILE, $cross_compile."objdump -dS --adjust-vma=$vmaoffset --start-address=$decodestart --stop-address=$decodestop $filename |") || die "Cannot start objdump";
+
+while (<FILE>) {
+	my $line = $_;
+	chomp($line);
+	if ($state == 0) {
+		if ($line =~ /^([a-f0-9]+)\:/) {
+			if (InRange($1, $target)) {
+				$state = 1;
+			}
+		}
+	}
+	if ($state == 1) {
+		if ($line =~ /^([a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]+)\:/) {
+			my $val = $1;
+			if (!InRange($val, $target)) {
+				last;
+			}
+			if ($val eq $target) {
+				$center = $counter;
+			}
+		}
+		$lines[$counter] = $line;
+
+		$counter = $counter + 1;
+	}
+}
+
+close(FILE);
+
+if ($counter == 0) {
+	print "No matching code found \n";
+	exit;
+}
+
+if ($center == -1) {
+	print "No matching code found \n";
+	exit;
+}
+
+my $start;
+my $finish;
+my $codelines = 0;
+my $binarylines = 0;
+# now we go up and down in the array to find how much we want to print
+
+$start = $center;
+
+while ($start > 1) {
+	$start = $start - 1;
+	my $line = $lines[$start];
+	if ($line =~ /^([a-f0-9]+)\:/) {
+		$binarylines = $binarylines + 1;
+	} else {
+		$codelines = $codelines + 1;
+	}
+	if ($codelines > 10) {
+		last;
+	}
+	if ($binarylines > 20) {
+		last;
+	}
+}
+
+
+$finish = $center;
+$codelines = 0;
+$binarylines = 0;
+while ($finish < $counter) {
+	$finish = $finish + 1;
+	my $line = $lines[$finish];
+	if ($line =~ /^([a-f0-9]+)\:/) {
+		$binarylines = $binarylines + 1;
+	} else {
+		$codelines = $codelines + 1;
+	}
+	if ($codelines > 10) {
+		last;
+	}
+	if ($binarylines > 20) {
+		last;
+	}
+}
+
+
+my $i;
+
+
+# start annotating the registers in the asm.
+# this goes from the oopsing point back, so that the annotator
+# can track (opportunistically) which registers got written and
+# whos value no longer is relevant.
+
+$i = $center;
+while ($i >= $start) {
+	$reglines[$i] = process_x86_regs($lines[$i], $center - $i);
+	$i = $i - 1;
+}
+
+$i = $start;
+while ($i < $finish) {
+	my $line;
+	if ($i == $center) {
+		$line =  "*$lines[$i] ";
+	} else {
+		$line =  " $lines[$i] ";
+	}
+	print $line;
+	if (defined($reglines[$i]) && length($reglines[$i]) > 0) {
+		my $c = 60 - length($line);
+		while ($c > 0) { print " "; $c = $c - 1; };
+		print "| $reglines[$i]";
+	}
+	if ($i == $center) {
+		print "<--- faulting instruction";
+	}
+	print "\n";
+	$i = $i +1;
+}
+
+sub usage {
+	print <<EOT;
+Usage:
+  dmesg | perl $0 [OPTION] [VMLINUX]
+
+OPTION:
+  -c, --cross-compile CROSS_COMPILE	Specify the prefix used for toolchain.
+  -m, --module MODULE_DIRNAME		Specify the module filename.
+  -h, --help				Help.
+EOT
+	exit;
+}