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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 6E39740006 X-Stat-Signature: sfpujemo4ietqdfe9iwoahuretp7uuwa X-Rspam-User: X-HE-Tag: 1786382478-397021 X-HE-Meta: U2FsdGVkX1/qiG/7XGZdsOMxPJyk0+1CbbbDDS6nuEC2mWA9NuafBdpeFNkvCe4K2sPLMsEbrveyIqCwHfU/qZqtsarw4qqz6mOTd5X7gBC/dHC4A0h0z1i7VPD8FLQc/RwHM+XNeSTQ2dYVvVuNlX7620AWA0hNuUlBoUXWfG1faYN438ZFBGlfiEaiWVDMyNpSFKhiMWPjfCfT1p6yybKDlSK/AhbYbitjNv35ZYzAEkCjGNFbg7aF9UeQVFPKPcJm5Sj8o+bN1EDlMwSivR1F9CBAsUAWKFHfbwrIYCqpkBOuaGwiY06LrXzJ5M3dvdjlSwRTNEwReK4VZwRq9vvXj/kS2/1dwrMdYDdO8P191cCfoZp/BKkdnuiTyhnTNYkujblo6aasvq/8jL94MuSTXzUhfWEmjjZPk7FHnLi55o897lUDCfShLwi34w5UMRlxKKCQZr90Nhn7mKyso0tbnjVflMClPMYiOo7hwqqpUk+MaNi6gH5Xc3x3Z28BnIJtghcC5ULgzBM+/Y5i+qbYRgI/cKwrCX3cTQqekLrGN/nIDN0NXqR4KV7jk70jOjNxTYzDjMqy2edHyvSu0wh8DlMHn5t4ukkDEIep+TgbDHEIu7bgNBTExnzY+LRSEmtdJWOLCNXbmK4BkjLRMrMRWVxxohDSDP6PFmXiFkkxA1zKK5cdOtwdRyuLFHuAYbP/MOqGZqtIQD5WzOrKd0iGmx5Zjd13nGKbEYUFnEhixDC6dyeW/AQkJhV8eF5Qa7bqPqL341gs9at5PlLHRaPek+psgrrirVUL5lBNBPstexZNdk/0BwFVn5YckzyvRFwDAwtvvL+31MmIba/E9ltmzob9eUmMGizmLzKlUvCEcr5Xr0As6tDg7lle17VumQUcfZ3d5rz0NuRxtwVJCK+r0F36oxat1lGFcxKxVxVmD9dcH+1GYBdQmq/f8Yj6xWhlZVTn7D9Dj+FUu8b WWIdhW0q 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Aug 10, 2026 at 09:14:04AM -0700, Eric Biggers wrote: > On Mon, Aug 10, 2026 at 09:00:11AM -0700, Christoph Hellwig wrote: > > On Thu, Aug 06, 2026 at 03:10:30PM -0700, Eric Biggers wrote: > > > To fix a deadlock, blk-crypto-fallback needs to be able to make fallible > > > mempool_alloc_bulk() allocations. > > > > It doesn't. fallible mempool allocations are a concept that doesn't > > make much sense. Please just go straight to the backing page allocator > > instead for callers that do not need the mempool guarantees. > > It does make sense. When alloc_pages_bulk() doesn't completely succeed, > there still might be pages available in the mempool. But they should not go to a caller that does not need the mempool. > blk_crypto_alloc_enc_bio() should try to take them before falling back > to scheduling the rescuer kworker. The rescuer encounters scheduling > overhead and is single-threaded, so it's slow and should be used only > when absolutely necessary. No, it should just try a regular non-bulk alloc_pages (and eventually alloc_pages_bulk should do that fallback for the callers, but that's a separate discussion).