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Revision e700898fa075c69b3ae02b702ab57fb75e1a82ec authored by Mike Kravetz on 12 December 2022, 23:50:41 UTC, committed by Andrew Morton on 21 December 2022, 22:31:52 UTC 
hugetlb: really allocate vma lock for all sharable vmas
 
Commit bbff39cc6cbc ("hugetlb: allocate vma lock for all sharable vmas")
removed the pmd sharable checks in the vma lock helper routines.  However,
it left the functional version of helper routines behind #ifdef
CONFIG_ARCH_WANT_HUGE_PMD_SHARE.  Therefore, the vma lock is not being
used for sharable vmas on architectures that do not support pmd sharing. 
On these architectures, a potential fault/truncation race is exposed that
could leave pages in a hugetlb file past i_size until the file is removed.

Move the functional vma lock helpers outside the ifdef, and remove the
non-functional stubs.  Since the vma lock is not just for pmd sharing,
rename the routine __vma_shareable_flags_pmd.

Link: https://lkml.kernel.org/r/20221212235042.178355-1-mike.kravetz@oracle.com
Fixes: bbff39cc6cbc ("hugetlb: allocate vma lock for all sharable vmas")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: James Houghton <jthoughton@google.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
1 parent 7ba594d
Raw File
scsi_debugfs.c 
// SPDX-License-Identifier: GPL-2.0
#include <linux/bitops.h>
#include <linux/seq_file.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_dbg.h>
#include "scsi_debugfs.h"

#define SCSI_CMD_FLAG_NAME(name)[const_ilog2(SCMD_##name)] = #name
static const char *const scsi_cmd_flags[] = {
	SCSI_CMD_FLAG_NAME(TAGGED),
	SCSI_CMD_FLAG_NAME(INITIALIZED),
	SCSI_CMD_FLAG_NAME(LAST),
};
#undef SCSI_CMD_FLAG_NAME

static int scsi_flags_show(struct seq_file *m, const unsigned long flags,
			   const char *const *flag_name, int flag_name_count)
{
	bool sep = false;
	int i;

	for_each_set_bit(i, &flags, BITS_PER_LONG) {
		if (sep)
			seq_puts(m, "|");
		sep = true;
		if (i < flag_name_count && flag_name[i])
			seq_puts(m, flag_name[i]);
		else
			seq_printf(m, "%d", i);
	}
	return 0;
}

void scsi_show_rq(struct seq_file *m, struct request *rq)
{
	struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
	int alloc_ms = jiffies_to_msecs(jiffies - cmd->jiffies_at_alloc);
	int timeout_ms = jiffies_to_msecs(rq->timeout);
	char buf[80] = "(?)";

	__scsi_format_command(buf, sizeof(buf), cmd->cmnd, cmd->cmd_len);
	seq_printf(m, ", .cmd=%s, .retries=%d, .result = %#x, .flags=", buf,
		   cmd->retries, cmd->result);
	scsi_flags_show(m, cmd->flags, scsi_cmd_flags,
			ARRAY_SIZE(scsi_cmd_flags));
	seq_printf(m, ", .timeout=%d.%03d, allocated %d.%03d s ago",
		   timeout_ms / 1000, timeout_ms % 1000,
		   alloc_ms / 1000, alloc_ms % 1000);
}
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