The patch titled Subject: zram-fix-synchronous-reads-fix has been added to the -mm mm-unstable branch. Its filename is zram-fix-synchronous-reads-fix.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/zram-fix-synchronous-reads-fix.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Christoph Hellwig <hch@xxxxxx> Subject: zram-fix-synchronous-reads-fix Date: Fri, 7 Apr 2023 09:22:24 +0200 turns out this doesn't even compile for PAGE_SIZE > 4096. Below is the fix, which also removes the #if and instead relies on compiler dead code elimination. I wonder if zram should (maybe optionally) also offer a 512 byte block size, so that we could also test the smaller than page size I/O path even on x86. Link: https://lkml.kernel.org/r/20230407072224.GA8982@xxxxxx Signed-off-by: Christoph Hellwig <hch@xxxxxx> Cc: Jens Axboe <axboe@xxxxxxxxx> Cc: Minchan Kim <minchan@xxxxxxxxxx> Cc: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/block/zram/zram_drv.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) --- a/drivers/block/zram/zram_drv.c~zram-fix-synchronous-reads-fix +++ a/drivers/block/zram/zram_drv.c @@ -764,7 +764,6 @@ release_init_lock: return ret; } -#if PAGE_SIZE != 4096 struct zram_work { struct work_struct work; struct zram *zram; @@ -775,7 +774,7 @@ struct zram_work { static void zram_sync_read(struct work_struct *work) { struct zram_work *zw = container_of(work, struct zram_work, work); - struct bio_bvec bv; + struct bio_vec bv; struct bio bio; bio_init(&bio, zw->zram->bdev, &bv, 1, REQ_OP_READ); @@ -794,6 +793,9 @@ static int read_from_bdev_sync(struct zr { struct zram_work work; + if (WARN_ON_ONCE(PAGE_SIZE != 4096)) + return -EIO; + work.page = page; work.zram = zram; work.entry = entry; @@ -805,14 +807,6 @@ static int read_from_bdev_sync(struct zr return 1; } -#else -static int read_from_bdev_sync(struct zram *zram, struct page *page, - unsigned long entry) -{ - WARN_ON(1); - return -EIO; -} -#endif static int read_from_bdev(struct zram *zram, struct page *page, unsigned long entry, struct bio *parent) _ Patches currently in -mm which might be from hch@xxxxxx are zram-remove-valid_io_request.patch zram-make-zram_bio_discard-more-self-contained.patch zram-simplify-bvec-iteration-in-__zram_make_request.patch zram-move-discard-handling-to-zram_submit_bio.patch zram-return-early-on-error-in-zram_bvec_rw.patch zram-refactor-highlevel-read-and-write-handling.patch zram-dont-use-highmem-for-the-bounce-buffer-in-zram_bvec_readwrite.patch zram-rename-__zram_bvec_read-to-zram_read_page.patch zram-directly-call-zram_read_page-in-writeback_store.patch zram-refactor-zram_bdev_read.patch zram-dont-pass-a-bvec-to-__zram_bvec_write.patch zram-refactor-zram_bdev_write.patch zram-pass-a-page-to-read_from_bdev.patch zram-dont-return-errors-from-read_from_bdev_async.patch zram-fix-synchronous-reads.patch zram-fix-synchronous-reads-fix.patch zram-return-errors-from-read_from_bdev_sync.patch