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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?tO3h3tcCpXhJLw5sOEyf0hKUexMlT8+cp3Ib+mLVPpgCw147eHDDrsc0fOT1?= =?us-ascii?Q?VFEppaMBu+B1kNRBzq9JAUbk33PG8BAlFuetHuKB/2v5I9lTDNqexLPkwEIo?= =?us-ascii?Q?5oWOIgBk9eu73nIvRxbuvVAdZI/+nqhuY/vzeiiOZ8JSzPb3Tkc63+VXEZZP?= =?us-ascii?Q?zz2RfNOesd4PLkjCDQXkN1+hTWhpsPzx5bflih40XTtlziNrfG4Ucc8Zlkzw?= =?us-ascii?Q?Gf2sw0OlNoPf5Iwn1UvLHkM7/N95eOd92SUcxL5qtV0cbP+jFUnKA/bfHiUQ?= =?us-ascii?Q?QElIgjkaHoTf2tSSKTcxjL9EtORJAJNhG5Uzr21mzXyam8iD4zcdDL2BOPkN?= =?us-ascii?Q?FSC1Th43atQoSM4uyYTkZ8FUf0cJaHNjLPoiG4K6sSssgVTm67zX3IEumXJy?= =?us-ascii?Q?TLplXxlGmG/I/48h2jII9JGmJNHfI+AFFYEnEj8gfVnxtyHIl6ZC+WIhYPBL?= =?us-ascii?Q?6cGxN5Yo919bwfuix5Y/Q5jyu10/Qbo7HWsQrW6YvhLPYsYGTfdlUtDB4Cq0?= =?us-ascii?Q?SV185MxaGu0KT1hKsxIFVtMseRcWA0RB8HTb7k/sh1FYECw0MXs7//DUR6Ur?= =?us-ascii?Q?aYPFdiDeDzN0zTuQbv1hPlOOuNepK3mDOnjyPUioQCtzaBEYt25OrX2Nhwgh?= =?us-ascii?Q?mfiJ54ZeppYwn6+RabXz17QECBAY+U1rXfJU0f8DvszMIJ2clKxNnOJKxsaM?= =?us-ascii?Q?sBEothLtgxp4j4q/kDDlru8/87+hngmSlf8LYUX3PI0k3Dab2U8CF6XB30iS?= =?us-ascii?Q?VTChLbLOnZUJG7++2e038PRDZve3H/saTKiHvn8Cm5x9VHSYF1KSZ63ab71L?= =?us-ascii?Q?BAcP1YU14ln1pabvpc6X8X6b0gCfM8IJLxXxsKy+878cCKJOhxq+ymTIDea2?= =?us-ascii?Q?HFhIMVyyo25FZwd6dnTpfNpgRR2wF9wXfPLLR3yaWXmbugl3/dIufHMdS16e?= =?us-ascii?Q?wO+IpJbANDO4O+3EJhZsCVVfI0DzVkCdT/YJj8KCpf4pPcFPnlIcPUDt3RPY?= =?us-ascii?Q?YDD/HEaR3S3j+7pGYUHULYNZD4Sy8Zhf2Jg4gQQHNS78P5m3yjwFyLFz5tpV?= =?us-ascii?Q?CXSzNKTuKbNERYvw5uhXspdEr2VPYQYZnR2Jn+s3bBYP+oKbqPnoVLyMwzcH?= =?us-ascii?Q?pD9NoSac4Wxil2NwulrGx1dCJFfhOEATLqAutOdIXNeeKR3rZMZVfHtj4eLS?= =?us-ascii?Q?a1JgMuaYPTsT2Cxme9AkdF23keES6hdfHb027kitN+cBMRkrBxO/guHb2ko/?= =?us-ascii?Q?/5W90t+QUR84kgcfC8U8BynkVNSXptr5nlqVZXCgI+gbrrGwy0mBgqemg6Zd?= =?us-ascii?Q?AcCaQAtEWHEDLGfgFqbsiwfxJk+soede7u0LQoWTiF77icqRDHx7jIWOSkef?= =?us-ascii?Q?MrESsEBMKxaQMj7mTWSVsDqoPhT3tYMtkVk7mEQs2utenwIcXB51BnahpUWd?= =?us-ascii?Q?av3DA/gOOUIVWxEcCNb5leUbN5yZangjq23ZPRuWubsxoWO7c535fyluKVfW?= =?us-ascii?Q?jAAkiQMzoUhG6O1056RKfZ6x1emdNEQKD2+CddgbxZ5cW4MspOAn+r002elL?= =?us-ascii?Q?9l63Or1lIdp6FtEh++t+k5DMW3KvY1V/QGODqxo2?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: dee2c4c1-b8ed-4696-17a5-08dd7690ca3f X-MS-Exchange-CrossTenant-AuthSource: CY5PR12MB6405.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Apr 2025 11:30:39.8437 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: iJfID7zNFky9yem+PDi9ys3g7h/zThT8MTyEymKwa9weh9Xi0RFPVP21JyMDLs2tjPc5x3JGeinxd3/pEiHkVA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB6919 Hi Breno, I already acked even the buggy version, so this one looks good. :) On Tue, Apr 08, 2025 at 04:09:02AM -0700, Breno Leitao wrote: > Replace kzalloc with kvzalloc for the exit_dump buffer allocation, which > can require large contiguous memory (up to order=9) depending on the BTW, from where this order=9 is coming from? exit_dump_len is 32K by default, but a BPF scheduler can arbitrarily set it to any value via ops->exit_dump_len, so it could be even bigger than an order 9 allocation. Thanks, -Andrea > implementation. This change prevents allocation failures by allowing the > system to fall back to vmalloc when contiguous memory allocation fails. > > Since this buffer is only used for debugging purposes, physical memory > contiguity is not required, making vmalloc a suitable alternative. > > Cc: stable@vger.kernel.org > Fixes: 07814a9439a3b0 ("sched_ext: Print debug dump after an error exit") > Suggested-by: Rik van Riel > Signed-off-by: Breno Leitao > Acked-by: Andrea Righi > --- > Changes in v2: > - Use kvfree() on the free path as well. > - Link to v1: https://lore.kernel.org/r/20250407-scx-v1-1-774ba74a2c17@debian.org > --- > kernel/sched/ext.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c > index 66bcd40a28ca1..db9af6a3c04fd 100644 > --- a/kernel/sched/ext.c > +++ b/kernel/sched/ext.c > @@ -4623,7 +4623,7 @@ static void scx_ops_bypass(bool bypass) > > static void free_exit_info(struct scx_exit_info *ei) > { > - kfree(ei->dump); > + kvfree(ei->dump); > kfree(ei->msg); > kfree(ei->bt); > kfree(ei); > @@ -4639,7 +4639,7 @@ static struct scx_exit_info *alloc_exit_info(size_t exit_dump_len) > > ei->bt = kcalloc(SCX_EXIT_BT_LEN, sizeof(ei->bt[0]), GFP_KERNEL); > ei->msg = kzalloc(SCX_EXIT_MSG_LEN, GFP_KERNEL); > - ei->dump = kzalloc(exit_dump_len, GFP_KERNEL); > + ei->dump = kvzalloc(exit_dump_len, GFP_KERNEL); > > if (!ei->bt || !ei->msg || !ei->dump) { > free_exit_info(ei); > > --- > base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8 > change-id: 20250407-scx-11dbf94803c3 > > Best regards, > -- > Breno Leitao >